Question: Which Midwestern Native American tribe, who settled near the confluence of the Missouri and the Mississippi rivers, is represented by mascot Chief Big Track at Arkansas State University?
Context: The Osage Nation ( ) ("Ni-u-kon-ska", "People of the Middle Waters") is a Midwestern Native American tribe of the Great Plains who historically dominated much of present-day Missouri, Arkansas, Kansas, and Oklahoma.  The tribe developed in the Ohio and Mississippi river valleys around 700 BC along with other groups of its language family.  They migrated west of the Mississippi after the 16th century due to wars with Iroquois invading the Ohio Valley from New York and Pennsylvania in a search for new hunting grounds.  The nations separated at that time, and the Osage settled near the confluence of the Missouri and the Mississippi rivers. Princess Mona Darkfeather (January 13, 1883 – September 3, 1977) was an American actress who starred in Native American and Western dramas.  Chief Big Thunder gave her the title “Princess” after the Blackfoot Native American Tribe made her a blood member.  During the silent era of motion pictures, from 1911 to 1917, she appeared in 102 movies.  Playing Native American characters in a dignified way, her most famous role was possibly as Prairie Flower in "The Vanishing Tribe" (1914). The 2002 Arkansas State Indians football team (now called the Arkansas State Red Wolves) represented Arkansas State University in the 2002 NCAA Division I FBS college football season as members of the Sun Belt Conference.  Under head coach Steve Roberts, the team compiled a record of 6 wins and 7 losses. Arkansas State University (also known as "A-State"")" is a public research university and is the flagship campus of the Arkansas State University System, the state's second largest college system and second largest university by enrollment.  It is located atop 1,376 acres (5.6 km2) on Crowley's Ridge at Jonesboro, Arkansas, United States.  The university marked its centennial year in 2009.  Arkansas State has Sun Belt rivalries with all West Division schools (Little Rock, Louisiana-Lafayette, Louisiana-Monroe, Texas State, and UT Arlington).  Their primary Sun Belt rivals are Little Rock and Louisiana-Monroe. The 2015 Arkansas State Red Wolves football team represented Arkansas State University in the 2015 NCAA Division I FBS football season.  They were led by head coach Blake Anderson, who was the first Red Wolves head coach since Steve Roberts in 2002 to return for a second season at Arkansas State (the three coaches between Roberts and Anderson all left for other head coaching jobs after a single season).  The Red Wolves, who play their home games at Centennial Bank Stadium in Jonesboro, Arkansas, are members of the Sun Belt Conference.  The Red Wolves finished the regular season 9–3, 8–0 in Sun Belt play to win their fourth Sun Belt Championship in five seasons.  In the New Orleans Bowl, the Red Wolves fell to Louisiana Tech 28–47. The ASU Indian Family was a trio of mascots for Arkansas State University in Jonesboro, Arkansas.  The family consists of Chief Big Track (named for a prominent Osage chief), an unnamed brave and an unnamed princess.  It is one of the few trios of athletics mascots for a university. The Ponca (Páⁿka iyé: Páⁿka or Ppáⁿkka pronounced ] ) are a Midwestern Native American tribe of the Dhegihan branch of the Siouan language group.  There are two federally recognized Ponca tribes: the Ponca Tribe of Nebraska and the Ponca Tribe of Indians of Oklahoma.  Their traditions and historical accounts suggest they originated as a tribe east of the Mississippi River in the Ohio River valley area and migrated west for game and as a result of Iroquois wars. The Waco (also spelled "Huaco " and "Hueco ") of the Wichita people is a Midwestern Native American tribe that inhabited northeastern Texas.  Today, they are enrolled members of the federally recognized Wichita and Affiliated Tribes, headquartered in Anadarko, Oklahoma. The Arkansas State Red Wolves baseball team (formerly the Arkansas State Indians) is a varsity intercollegiate athletic team of Arkansas State University in Jonesboro, Arkansas, United States.  The team is a member of the Sun Belt Conference, which is part of the National Collegiate Athletic Association's Division I.  Arkansas State's first baseball team was fielded in 1925.  The team plays its home games at Tomlinson Stadium–Kell Field in Jonesboro, Arkansas.  The Red Wolves are coached by Tommy Raffo. The Omaha are a federally recognized Midwestern Native American tribe who reside on the Omaha Reservation in northeastern Nebraska and western Iowa, United States.  The Omaha Indian Reservation lies primarily in the southern part of Thurston County and northeastern Cuming County, Nebraska, but small parts extend into the northeast corner of Burt County and across the Missouri River into Monona County, Iowa.  Its total land area is 796.355 km2 and a population of 5,194 was recorded in the 2000 census.  Its largest community is Macy.
Answer: The Osage Nation