World Series The World Series is the annual championship series of North American - based Major League Baseball ( MLB ) , played since 1903 between the American League ( AL ) and National League ( NL ) team champions . The winner of the World Series championship is determined through a best - of - seven playoff and the winning team is awarded the Commissioner ' s Trophy . As the series is played in October , which falls during autumn in North America , MLB also refers to it as the Fall Classic . The most recent World Series was won by the San Francisco Giants , who defeated the Detroit Tigers in a four - game sweep in 2012 . The New York Yankees of the AL have played in 40 World Series and won 27 , the Oakland / Philadelphia Athletics have played in 14 and won 9 , and the Boston Red Sox have played in 12 and won 7 , including the first World Series . In the NL , the San Francisco / New York Giants have appeared in 19 World Series and won 7 , the St . Louis Cardinals have played in 18 and won 11 , and the Los Angeles / Brooklyn Dodgers have appeared in 18 and won 6 . Precursors to the modern World Series ( 1857 – 1902 ) . The original World Series . Until the formation of the American Association in 1882 as a second major league , the National Association of Professional Base Ball Players ( 1871 – 75 ) and then the National League ( founded 1876 ) represented the top level of organized baseball in the United States . All championships went to whoever had the best record at the end of the season , without a postseason series being played . Starting in 1884 and going through 1890 , the National League and the American Association faced each other in a series of games at the end of the season to determine an overall champion . These matchups were disorganized in comparison to the modern Series : games played ranged from as few as three in 1884 ( Providence defeated New York three games to zero ) , to a high of 15 in 1887 ( Detroit beat St . Louis 10 games to five ) , and both the 1885 and 1890 Series ended in ties , each team having won three games with one tie game . The series were promoted and referred to as " The Championship of the United States " , " World ' s Championship Series " , or " World ' s Series " for short . The 19th - century competitions are , however , not officially recognized as part of World Series history by Major League Baseball , as it considers 19th - century baseball to be a prologue to the modern baseball era . Until about 1960 , some sources treated the 19th - century Series on an equal basis with the post - 19th - century series . After about 1930 , however , many authorities list the start of the World Series in 1903 and discuss the earlier contests separately . 1892 – 1900 : " The Monopoly Years " . Following the collapse of the American Association after the 1891 season , four of its clubs were admitted to the National League , which was again the only major league . The league championship was awarded in 1892 by a playoff between half - season champions . This scheme was abandoned after one season . Beginning in 1893 — and continuing until divisional play was introduced in 1969 — the pennant was awarded to the first - place club in the standings at the end of the season . For four seasons , 1894 – 97 , the league champions played the runners - up in the post season championship series called the Temple Cup . A second attempt at this format was the Chronicle - Telegraph Cup series , which was played only once , in 1900 . In 1901 , the American League was formed as a second major league . No championship series were played in 1901 or 1902 as the National and American Leagues fought each other for business supremacy . Modern World Series ( 1903 – present ) . First attempt . After two years of bitter competition and player raiding ( in 1902 , the AL and NL champions even went so far as to challenge each other to a tournament in " football " after the end of the baseball season ) , the National and American Leagues made peace and , as part of the accord , several pairs of teams squared off for interleague exhibition games after the 1903 season . These series were arranged by the participating clubs , as the 1880s World ' s Series matches had been . One of them matched the two pennant winners , Pittsburgh Pirates of the NL and Boston ( later known as the Red Sox ) of the AL ; that one is known as the 1903 World Series . It had been arranged well in advance by the two owners , as both teams were league leaders by large margins . Boston upset Pittsburgh by 5 games to 3 , winning with pitching depth behind Cy Young and Bill Dinneen and with the support of the band of Royal Rooters . The Series brought much civic pride to Boston and proved the new American League could beat the Nationals . Simon Winchester argues the World Series was named for the New York World newspaper , but this view is disputed . Boycott of 1904 . The 1904 Series , if it had been held , would have been between the AL ' s Boston Americans ( Boston Red Sox ) and the NL ' s New York Giants ( now the San Francisco Giants ) . At that point there was no governing body for the World Series nor any requirement that a Series be played . Thus the Giants ' owner , John T . Brush , refused to allow his team to participate in such an event , citing the " inferiority " of the upstart American League . John McGraw , the Giants ' manager , even went so far as to say that his Giants were already " world champions " since they were the champions of the " only real major league " . At the time of the announcement , their new cross - town rivals , the New York Highlanders ( now the NY Yankees ) , were leading the AL , and the prospect of facing the Highlanders did not please Giants management . Boston won on the last day of the season , and the leagues had previously agreed to hold a World ' s Championship Series in 1904 , but it was not binding , and Brush stuck to his original decision . In addition to political reasons , Brush also factually cited the lack of rules under which money would be split , where games would be played , and how they would be operated and staffed . During the winter of 1904 – 05 , however , feeling the sting of press criticism , Brush had a change of heart and proposed what came to be known as the " Brush Rules , " under which the series were played subsequently . One rule was that player shares would come from a portion of the gate receipts for the first four games only . This was to discourage teams from " fixing " early games in order to prolong the series and make more money . Receipts for later games would be split among the two clubs and the National Commission , the governing body for the sport , which was able to cover much of its annual operating expense from World Series revenue . Most importantly , the now - official and compulsory World ' s Series matches were operated strictly by the National Commission itself , not by the participating clubs . With the new rules in place and the National Commission in control , McGraw ' s Giants decided to show up for the 1905 Series , and beat the Philadelphia A ' s four games to one . The Series was held in every subsequent season for 89 years . The list of post - season rules evolved over time . In 1925 , Brooklyn owner Charles Ebbets convinced others to adopt as a permanent rule the 2 – 3 – 2 pattern used in 1924 . Prior to 1924 , the pattern had been to alternate by game or to make another arrangement convenient to both clubs . The 2 – 3 – 2 pattern is still in use ( except for the 1943 and 1945 World Series following a 3 – 4 pattern ) . ( The 2 – 3 – 2 pattern was used in 1944 because both teams were based in the same home stadium . ) 1919 : The fix . Gambling and game - fixing had been a problem in professional baseball from the beginning ; star pitcher Jim Devlin was banned for life in 1877 , when the National League was just two years old . Baseball ' s gambling problems came to a head in 1919 , when seven players of the Chicago White Sox were alleged to have conspired to throw the 1919 World Series . The Sox had won the Series in 1917 and were heavy favorites to beat the Cincinnati Reds in 1919 , but first baseman Chick Gandil had other plans . Gandil , in collaboration with gambler Joseph " Sport " Sullivan , approached his teammates and got six of them to agree to throw the Series : starting pitchers Eddie Cicotte and Lefty Williams , shortstop Swede Risberg , left fielder Shoeless Joe Jackson , center fielder Happy Felsch , and utility infielder Fred McMullin . Third baseman Buck Weaver knew of the fix but declined to participate , hitting . 324 for the series from 11 hits and committing no errors in the field . The Sox , who were promised $ 100 , 000 for cooperating , proceeded to lose the Series in eight games , pitching poorly , hitting poorly and making many errors . Though he took the money , Jackson insisted to his death that he played to the best of his ability in the series ( he was the best hitter in the series , but had markedly worse numbers in the games the White Sox lost ) . During the Series , writer and humorist Ring Lardner had facetiously called the event the " World ' s Serious " . The Series turned out to indeed have serious consequences for the sport . After rumors circulated for nearly a year , the players were suspended in September 1920 . The " Black Sox " were acquitted in a criminal conspiracy trial . However , baseball in the meantime had established the office of Commissioner in an effort to protect the game ' s integrity , and the first commissioner , Kenesaw Mountain Landis , banned all of the players involved , including Weaver , for life . The White Sox would not win a World Series again until 2005 . The events of the 1919 Series , segueing into the " live ball " era , marked a point in time of change of the fortunes of several teams . The two most prolific World Series winners to date , the New York Yankees and the St . Louis Cardinals , did not win their first championship until the 1920s ; and three of the teams that were highly successful prior to 1920 ( the Boston Red Sox , Chicago White Sox and the Chicago Cubs ) went the rest of the 20th century without another World Series win . The Red Sox and White Sox finally won again in 2004 and 2005 , respectively . The Cubs are still waiting for their next trophy , and have not appeared in the Fall Classic since 1945 , the longest drought of any MLB club . New York Yankees dynasty ( 1920 – 1964 ) . The New York Yankees purchased Babe Ruth from the Boston Red Sox after the 1919 season , appeared in their first World Series two years later in 1921 , and became frequent participants thereafter . Over a period of 45 years from 1920 to 1964 , the Yankees played in 29 World Series championships , winning 20 . The team ' s dynasty reached its apex between 1947 and 1964 , when the Yankees reached the World Series 15 times in eighteen years ( missing only 1948 , 1954 , and 1959 ) , winning ten . From 1949 to 1953 , the Yankees won the World Series five years in a row ; from 1936 – 1939 the Yankees won four World Series Championships in a row . There are only two other occasions when a team has won at least three consecutive World Series : 1972 to 1974 by the Oakland Athletics , and 1998 to 2000 by the New York Yankees . 1947 – 1964 : New York City teams dominate World Series play . In an 18 - year span from 1947 to 1964 , except for 1948 and 1959 , the World Series was played in New York City , featuring at least one of the three teams located in New York at the time . The Dodgers and Giants moved to California after the 1957 season , leaving the Yankees as the lone team in the city until the Mets were enfranchised in 1962 . During this period , other than 1948 , 1954 , and 1959 , the Yankees represented the American League in the world Series . In the years 1947 , 1949 , 1951 – 1953 , and 1955 – 1956 , both teams in the World Series were from New York , with the Yankees playing against either the Dodgers or Giants . The World Series in California . In 1957 , the Brooklyn Dodgers and New York Giants took their long - time rivalry to the west coast , moving to Los Angeles and San Francisco , respectively , bringing Major League Baseball west of St . Louis and Kansas City . The Dodgers were the first of the two clubs to contest a World Series on the west coast , defeating the Chicago White Sox in 1959 . The 1962 Giants made their first World Series appearance in San Francisco , losing to the Yankees . The Dodgers made three World Series appearances in the 1960s : a 1963 win over the Yankees , a 1965 win over the Minnesota Twins and 1966 loss to the Baltimore Orioles . In 1968 , the Kansas City Athletics relocated to Oakland and the following year 1969 , the National League granted a franchise to San Diego as the San Diego Padres . The A ' s became a powerful dynasty in 1970 ' s major league baseball while the Padres have only two World Series appearances : a 1984 loss to the Detroit Tigers and a 1998 loss to the Yankees . 1969 : League Championship Series . Prior to 1969 , the National League and the American League each crowned its champion ( the " pennant winner " ) based on the best win - loss record at the end of the regular season . A structured playoff series began in 1969 , when both the National and American Leagues were reorganized into two divisions each , East and West . The two division winners within each league played each other in a best - of - five League Championship Series to determine who would advance to the World Series . In 1985 , the format changed to best - of - seven . The National League Championship Series ( NLCS ) and American League Championship Series ( ALCS ) , since the expansion to best - of - seven , are always played in a 2 – 3 – 2 format : Games 1 , 2 , 6 and 7 are played in the stadium of the team that has home - field advantage , and Games 3 , 4 and 5 are played in the stadium of the team that does not . 1971 : World Series at night . MLB night games started being held in 1935 by the Cincinnati Reds , but the World Series remained a strictly daytime event for years thereafter . In the final game of the 1949 World Series , a Series game was finished under lights for the first time . The first scheduled night World Series game was Game 4 of the 1971 World Series at Three Rivers Stadium . Afterward , World Series games were frequently scheduled at night , when television audiences were larger . Game 6 of the 1987 World Series was the last World Series game played in the daytime , indoors at the Metrodome in Minnesota . ( The last World Series played outdoors during the day was the final game of the 1984 series in Detroit ' s Tiger Stadium . ) 1972 – 1978 : Three of a kind . During this seven - year period , only three teams won the World Series : the Oakland Athletics from 1972 – 1974 , Cincinnati Reds in 1975 and 1976 , and New York Yankees in 1977 and 1978 . This is the only time in World Series history in which three teams have won consecutive series in succession . This period was book - ended by World Championships for the Pittsburgh Pirates , in 1971 and 1979 . However , the Baltimore Orioles made three consecutive World Series appearances : 1969 ( losing to the " amazing " eight - year old franchise New York Mets ) , 1970 ( beating the Reds in their first World Series appearance of the decade ) and 1971 ( losing to the Pittsburgh Pirates , as well their 1979 appearance , when they again lost to the Pirates ) , and the Los Angeles Dodgers ' back - to - back World Series appearances in 1977 and 1978 ( both losses to the New York Yankees ) , as well in 1974 losing against the cross - state rival Oakland A ' s . 1976 : The Designated Hitter comes to the World Series . The National and American Leagues operated under essentially identical rules until 1973 , when the American League adopted the designated hitter rule , allowing its teams to use another hitter to bat in place of the ( usually ) weak - hitting pitcher . The National League did not adopt the DH rule . This presented a problem for the World Series , whose two contestants would now be playing their regular - season games under different rules . From 1973 to 1975 , the World Series did not include a DH . Starting in 1976 , the World Series allowed for the use of a DH in even - numbered years only . ( The Cincinnati Reds swept the 1976 Series in four games , using the same nine - man lineup in each contest . ) Finally , in 1986 , baseball adopted the current rule in which the DH is used for World Series games played in the AL champion ' s park but not the NL champion ' s . Thus , the DH rule ' s use or non - use can help the team that has home - field advantage . 1984 : Anderson becomes first to win in both leagues . The 1984 Detroit Tigers gained distinction as just the third team in major league history ( after the 1927 New York Yankees and 1955 Brooklyn Dodgers ) to lead a season wire - to - wire , from opening day through the World Series . In the process , Tigers ' skipper Sparky Anderson became the first manager to win a World Series title in both leagues , having previously won in 1975 and 1976 with the Cincinnati Reds . 1989 : Earthquake . When the 1989 World Series began , it was notable chiefly for being the first ever World Series matchup between the two San Francisco Bay Area teams , the San Francisco Giants and Oakland Athletics . Oakland won the first two games at home , and the two teams crossed the bridge to San Francisco to play Game 3 on Tuesday , October 17 . ABC ' s broadcast of Game 3 began at 5 pm local time , approximately 30 minutes before the first pitch was scheduled . At 5 : 04 , while broadcasters Al Michaels and Tim McCarver were narrating highlights and the teams were warming up , the Loma Prieta earthquake occurred ( having a surface - wave magnitude of 7 . 1 with an epicenter ten miles ( 16 km ) northeast of Santa Cruz , CA ) . The earthquake caused substantial property and economic damage in the Bay Area and killed 63 people . Television viewers saw the video signal deteriorate and heard Michaels say " I ' ll tell you what , we ' re having an earth - - " before the feed from Candlestick Park was lost . Fans filing into the stadium saw Candlestick sway visibly during the quake . Television coverage later resumed , using backup generators , with Michaels becoming a news reporter on the unfolding disaster . Approximately 30 minutes after the earthquake , Commissioner Fay Vincent ordered the game to be postponed . Fans , workers , and the teams evacuated a blacked out ( although still sunlit ) Candlestick . Game 3 was finally played on October 27 , and Oakland won that day and the next to complete a four - game sweep . 1992 – 1993 The World Series goes North . World Series games were contested outside of the United States for the first time in 1992 , with the Toronto Blue Jays defeating the Atlanta Braves in six games . The World Series returned to Canada in 1993 , with the Blue Jays victorious again , this time against the Philadelphia Phillies in six games . No other Series has featured a team from outside of the United States . Toronto is the only expansion team to win successive World Series titles . The 1993 World Series was also notable for being only the second championship concluded by a home run and the first concluded by a come - from - behind homer , after Joe Carter ' s three - run shot in the bottom of the ninth inning sealed an 8 – 6 Toronto win in Game 6 . The first Series to end with a homer was the 1960 World Series , when Bill Mazeroski hit a ninth - inning solo shot in Game 7 to win the championship for the Pittsburgh Pirates . 1994 : League Division Series . In 1994 , each league was restructured into three divisions , with the three division winners and the newly introduced wild card winner advancing to a best - of - five playoff round ( the " division series " ) , the National League Division Series ( NLDS ) and American League Division Series ( ALDS ) . The team with the best league record is matched against the wild card team , unless they are in the same division , in which case , the team with the second - best record plays against the wild card winner . The remaining two division winners are pitted against each other . The winners of the series in the first round advance to the best - of - seven NLCS and ALCS . Due to a players ' strike , however , the NLDS and ALDS were not played until 1995 . Beginning in 1998 , home field advantage was given to the team with the better regular season record , with the exception that the Wild Card team cannot get home - field advantage . 1994 – 95 strike . After the boycott of 1904 , the World Series was played every year until 1994 despite World War I , the global influenza pandemic of 1918 – 19 , the Great Depression of the 1930s , America ' s involvement in World War II , and even an earthquake in the host cities of the 1989 World Series . A breakdown in collective bargaining led to a strike in August 1994 and the eventual cancellation of the rest of the season , including the playoffs . As the labor talks began , baseball franchise owners demanded a salary cap in order to limit payrolls , the elimination of salary arbitration , and the right to retain free agent players by matching a competitor ' s best offer . The Major League Baseball Players Association ( MLBPA ) refused to agree to limit payrolls , noting that the responsibility for high payrolls lay with those owners who were voluntarily offering contracts . One difficulty in reaching a settlement was the absence of a commissioner . When Fay Vincent was forced to resign in 1992 , owners did not replace him , electing instead to make Milwaukee Brewers owner Bud Selig acting commissioner . Thus the commissioner , responsible for ensuring the integrity and protecting the welfare of the game , was an interested party rather than a neutral arbiter , and baseball headed into the 1994 work stoppage without an independent commissioner for the first time since the office was founded in 1920 . The previous collective bargaining agreement expired on December 31 , 1993 , and baseball began the 1994 season without a new agreement . Owners and players negotiated as the season progressed , but owners refused to give up the idea of a salary cap and players refused to accept one . On August 12 , 1994 , the players went on strike . After a month passed with no progress in the labor talks , Selig canceled the rest of the 1994 season and the postseason on September 14 . The World Series was not played for the first time in 90 years . The Montreal Expos were the best team in baseball at the time of the stoppage , with a record of 74 – 40 . ( Since their founding in 1969 , the Expos , now the Washington Nationals , have never played in a World Series . ) The labor dispute lasted into the spring of 1995 , with owners beginning spring training with replacement players . However , the MLBPA returned to work on April 2 , 1995 after a federal judge , future U . S . Supreme Court justice Sonia Sotomayor , ruled that the owners had engaged in unfair labor practices . The season started on April 25 and the 1995 World Series was played as scheduled , with Atlanta beating Cleveland four games to two . All - Star Game and home - field advantage . Prior to 2003 , home - field advantage in the World Series alternated from year to year between the NL and AL . After the 2002 Major League Baseball All - Star Game ended in a tie , MLB decided to award home - field advantage in the World Series to the winner of the All - Star Game . Originally implemented as a two - year trial from 2003 to 2004 , the practice has been extended indefinitely . The American League won every All - Star Game since this change until 2010 and thus has enjoyed home - field advantage from 2002 , when it also had home - field advantage based on the alternating schedule , through 2009 . As of the conclusion of the 2010 World Series , the AL and NL had each won the World Series four times since the All - Star Game was used to determine home - field advantage , though no Series from 2003 – 2010 had gone the full seven games . The 2011 World Series was the first of the All - Star Game home - field advantage era to go the full seven games . Modern World Series appearances by franchise . World Series record by team or franchise , 1903 – 2012 . Notes . American League ( AL ) teams have won 62 of 108 World Series completed so far ( 62 – 46 = 57 % – 43 % or 4 : 3 ) . The New York Yankees have won 27 , accounting for exactly 25 % of all the series played and about 44 % of the 62 wins by American League teams . The St . Louis Cardinals have won 11 World Series , or just over 10 % of all victories and just under 24 % of the 46 National League victories . When the first modern World Series was played in 1903 , eight teams constituted the American League ( founded 1901 ) and another eight constituted the National League ( founded 1876 ) . All sixteen of the 1903 teams have won at least two Series . No new team joined either league until 1961 ; fourteen " expansion team s " have joined since then . Twelve of the fourteen have played in a World Series ( all but the Mariners and the Expos / Nationals ) , and 20 of the 51 Series contested from 1961 to 2012 ( 39 % ) have featured an expansion team , always paired with one of the sixteen 1903 teams . The expansion teams have won 9 of the 20 Series in which they have played ( 45 % ) and one - twelfth of all 108 Series played since 1903 . Team patterns in the World Series . This information is up to date through the 2012 World Series : Local rivalries . When two teams share the same state or metropolitan area , fans often develop strong loyalties to one and antipathies towards the other , sometimes building on already - existing rivalries between cities or neighborhoods . Before the introduction of interleague play in 1997 , the only opportunity for two teams in different leagues to face each other in official competition would have been in a World Series . Cross - town Series . The first city to host an entire World Series is Chicago in 1906 , when the Chicago White Sox beat the Chicago Cubs in six games . Fourteen " Subway Series " have been played entirely within New York City , all including the American League ' s New York Yankees . Thirteen of them matched the Yankees with either the New York Giants or the Brooklyn Dodgers of the National League . The initial instances occurred in 1921 and 1922 , when the Giants beat the Yankees in consecutive World Series that were not technically " subway series " since the teams shared the Polo Grounds as their home ballpark . The last Subway Series involving the original New York ballclubs came in 1956 , when the Yankees beat the Dodgers . The trio was separated in 1958 when the Dodgers and Giants moved to California , and an all - NY Series did not recur until 2000 , when the Yankees defeated the New York Mets in five games . The last World Series played entirely in one ballpark was the 1944 " Streetcar Series " between the St . Louis Cardinals and the St . Louis Browns . The Cardinals won in six games , all held in their shared home , Sportsman ' s Park . The 1989 World Series , sometimes called the " Bay Bridge Series " or the " BART Series " ( after the connecting transit line ) , featured the Oakland Athletics and the San Francisco Giants , teams that play just across San Francisco Bay from each other . The series is most remembered for the major earthquake that struck the San Francisco Bay Area just before game 3 was scheduled to begin . The quake caused significant damage to both communities and severed the Bay Bridge that connects them , forcing the postponement of the series . Play resumed ten days later , and the A ' s swept the Giants in four games . Other neighborhood rivalries . For the other two cities where a cross - town competition , connected by local transit , was once possible — Boston ( until 1953 when the Braves moved to Milwaukee ) and Philadelphia ( until 1955 when the Athletics moved to Kansas City ) — an October meeting came closest to occurring in 1948 , when the Boston Braves won the National League pennant , and their nearby rivals , the Boston Red Sox , tied for the American League pennant on the last day of the season . However , the Cleveland Indians defeated the Red Sox in a one - game playoff , and then defeated the Braves in the Series . Before the modern World Series era , an opportunity for an all - Boston contest between league champions was missed . In 1891 , the Braves , then the Boston Beaneaters , of the National League declined to play the Boston Reds of the soon - to - dissolve American Association . The only meeting of neighbouring teams in the pre - modern World Series era occurred in 1889 , when the National League ' s champion , the New York Giants , defeated the American Association ' s champion , the Brooklyn Bridegrooms . Other cross - state rivalries . The historic rivalry between Northern and Southern California added to the interest in the Oakland Athletics - Los Angeles Dodgers series in 1974 and 1988 and in the San Francisco Giants ' series against the then - Anaheim Angels in 2002 . The two Los Angeles area teams have never competed against each other in a Series , nor has the only team in San Diego , the Padres , ever played a Series against another California team . Both the Angels and Dodgers appeared in their respective League Championship Series in 2009 , but both teams failed to advance – the Dodgers lost to the Philadelphia Phillies , and the Angels lost to the eventual World Series champion New York Yankees . Other than the St . Louis World Series of 1944 , the only postseason tournament entirely within Missouri was the I - 70 Series in 1985 ( named for the Interstate Highway connecting the two cities ) between the St . Louis Cardinals and the Kansas City Royals , who won at home in the seventh game . While the Philadelphia Athletics never played in World Series against either the Philadelphia Phillies or the Pittsburgh Pirates , they did engage in a popular semi - annual tradition of preseason City Series exhibition games against the Phillies . During their 13 years in Kansas City ( 1955 – 1967 ) , the A ' s never faced their then - cross state rival , the St . Louis Cardinals in a World Series . In the only other states that also have or once had teams in both major leagues since 1903 , there has never been a World Series between teams in Florida ( Miami Marlins and Tampa Bay Rays ) , Texas ( Houston Astros and Texas Rangers ) or Ohio ( Cincinnati Reds and Cleveland Indians ) . The last pair came closest to facing each other when the Indians won the 1995 American League pennant in the same year that the Reds lost the NL Championship Series . While not in the same state , the Baltimore Orioles and Washington Nationals could be considered neighborhood rivals , with their home cities being only 40 miles apart . However , a World Series between these two neighbors has yet to occur . The closest this came to occurring was 2012 , when both the Orioles and Nationals played in post season for the same year for the first time . Both teams lost their division series — the Orioles to the Yankees , who went on to be swept by the Tigers in the American League Championship Series , while the Nationals lost to the Cardinals , who were likewise defeated in the National League Championship Series by the Giants . The original sixteen teams . At the time the first modern World Series began in 1903 , each league had eight clubs , all of which survive today ( although sometimes in a different city or with a new nickname ) , comprising the " original sixteen " . International participation . Despite its name , the World Series remains solely the championship of the major - league baseball teams in the United States and Canada , although MLB , its players , and North American media sometimes informally refer to World Series winners as " world champions of baseball . " The United States , Canada and Mexico ( " Liga Méxicana de Béisbol " , established 1925 ) were the only professional baseball countries until a few decades into the 20th century . The first Japanese professional baseball efforts began in 1920 . The current Japanese leagues date from the late 1940s ( after World War II ) . Various Latin American leagues also formed around that time . By the 1990s , baseball was played at a highly skilled level in many countries . Reaching North America ' s high - salary major leagues is the goal of many of the best players around the world , which gives a strong international flavor to the Series . Many talented players from Latin America , the Caribbean , the Pacific Rim , and elsewhere now play in the majors . One notable exception is Cuban citizens , because of the political tensions between the US and Cuba since 1959 ( yet a number of Cuba ' s finest ballplayers have still managed to defect to the United States over the past half - century to play in the American professional leagues ) . Japanese professional players also have a difficult time coming to the North American leagues . They become free agents only after nine years playing service in NPB , although their Japanese teams may at any time " post " them for bids from MLB teams , which commonly happens at the player ' s request . Several tournaments feature teams composed only players from one country , similar to national teams in other sports . The World Baseball Classic , sponsored by Major League Baseball , uses a format similar to the FIFA World Cup to promote competition between nations every four years . The International Baseball Federation also sponsored a Baseball World Cup to crown a world champion . But as these teams do not feature the best talent from each nation , the public generally does not give much weight to the result of these tournaments . The Caribbean Series features competition among the league champions from Mexico , Puetro Rico , the Dominican Republic , and Venezuela but unlike the FIFA Club World Cup , there is no club competition that feature champions from all professional leagues across the world .