Jogaila Jogaila , later ( c . 1351 / 1362 – 1 June 1434 ) was Grand Duke of Lithuania ( 1377 – 1434 ) , King of the Kingdom of Poland ( 1386 – 1399 ) , and then sole King of Poland ( 1399 – 1434 ) . He ruled in Lithuania from 1377 , at first with his uncle Kęstutis . In 1386 in Kraków he was baptized as Władysław , married the young Queen regnant Jadwiga of Poland , and was crowned King of Poland as Władysław II Jagiełło . In 1387 he converted Lithuania to Christianity . His own reign in Poland started in 1399 , upon death of Queen Jadwiga , and lasted a further thirty - five years and laid the foundation for the centuries - long Polish – Lithuanian union . He was the founder of the Jagiellonian dynasty in Poland that bears his name and was the heir to the already established house of Gediminids in the Grand Duchy of Lithuania . These royal dynasties ruled both states until 1572 , and became one of the most influential dynasties in the late medieval and early modern Central and Eastern Europe . During his reign , the Polish - Lithuanian state was the largest state in the Christian world . Jogaila was the last pagan ruler of medieval Lithuania . After he became King of Poland , as a result of Union of Krewo , the newly formed Polish - Lithuanian union confronted the growing power of the Teutonic Knights . The allied victory at the Battle of Grunwald in 1410 , followed by the Peace of Thorn ( 1411 ) , secured the Polish and Lithuanian borders and marked the emergence of the Polish – Lithuanian alliance as a significant force in Europe . The reign of Władysław II Jagiełło extended Polish frontiers and is often considered the beginning of Poland ' s " Golden Age " . Early life . Lithuania . Little is known of Jogaila ' s early life , and even his date of birth is not certain . Previously historians gave his date of birth as 1352 , but some recent research suggests a later date — about 1362 . He was a descendant of the Gediminid dynasty and was probably born in Vilnius . His parents were Algirdas , Grand Duke of Lithuania , and his second wife , Uliana , daughter of Alexander I , Grand Prince of Tver . The Grand Duchy of Lithuania to which Jogaila succeeded as Grand Duke in 1377 was a political entity composed of two leading , but very different nationalities and two political systems : ethnic Lithuania in the north - west and the vast Ruthenia n territories of former Kievan Rus ' , comprising the lands of modern Ukraine , Belarus , and parts of western Russia . At first , Jogaila — like his father — based his rule in the southern and eastern territories of Lithuania , while his uncle , Kęstutis , the Duke of Trakai , continued to rule the north - western region . Jogaila ' s succession , however , soon placed this system of dual rule under strain . At the start of his reign , Jogaila was preoccupied with unrest in the Lithuanian Rus ' lands . In 1377 – 78 , Andrei of Polotsk , the eldest son of Algirdas , challenged Jogaila ' s authority and sought to become Grand Duke . In 1380 , Andrei and another brother , Dmitry , sided with Prince Dmitri of Moscow against Jogaila ' s alliance with emir Mamai , " de facto " khan of the Golden Horde . Jogaila failed to support Mamai , lingering in the vicinity of the battlefield , which led to Mamai ' s army ' s significant defeat at the hands of Prince Dmitri in the Battle of Kulikovo . The Muscovite quite Pyrrhic victory over the Golden Horde , in the long term , signified , however , the beginning of a slow climb to power by the Grand Duchy of Moscow , which became within a century the most serious rival and threat to the integrity , well - being and survival of Lithuania . However , in 1380 Muscovy was awfully weakened by tremendous losses suffered during the battle and thus , in the same year , Jogaila was free to begin a struggle for supremacy with Kęstutis . In the north - west , Lithuania faced constant armed incursions from the Teutonic Knights — founded after 1226 to fight and convert the pagan Baltic tribes of Prussians , Yotvingians and Lithuanians . In 1380 , Jogaila secretly concluded the secret Treaty of Dovydiškės , directed against Kęstutis . When Kęstutis discovered the plan , the Lithuanian Civil War began . He seized Vilnius , overthrew Jogaila , and pronounced himself grand duke in his place . In 1382 , Jogaila raised an army from his father ' s vassals and confronted Kęstutis near Trakai . Kęstutis and his son Vytautas entered Jogaila ' s encampment for negotiations but were tricked and imprisoned in the Kreva Castle , where Kęstutis was found dead , probably murdered , a week later . Vytautas escaped to the Teutonic fortress of Marienburg and was baptised there under the name Wigand . Jogaila formulated the Treaty of Dubysa , which rewarded the Knights for their aid in defeating Kęstutis and Vytautas by promising Christianisation and granting them Samogitia west of the Dubysa river . However , when Jogaila failed to ratify the treaty , the Knights invaded Lithuania in the summer of 1383 . In 1384 , Jogaila reconciled with Vytautas promising to return his patrimony in Trakai . Vytautas then turned against the Knights , attacking and looting several Prussian castles . Baptism and marriage . Jogaila ' s Russian mother Uliana of Tver urged him to marry Sofia , daughter of Prince Dmitri of Moscow , who required him first to convert to Orthodoxy . That option , however , was unlikely to halt the crusades against Lithuania by the Teutonic Knights , who regarded Orthodox Christians as schismatics and little better than heathens . Jogaila chose therefore to accept a Polish proposal to become a Catholic and marry the eleven - year - old Queen Jadwiga of Poland . The nobles of Malopolska made this offer to Jogaila for many reasons . They wanted to neutralize the dangers posed by Lithuania itself and to secure the fertile territories of Galicia – Volhynia . The Polish nobles saw the offer as an opportunity for increasing their privileges and avoiding Austrian influence , brought by Jadwiga ' s previous fiancé William , Duke of Austria . On 14 August 1385 in Kreva Castle , Jogaila confirmed his prenuptial promises in the Union of Krewo ( Union of Kreva ) . The promises included the adoption of Christianity , repatriation of lands " stolen " from Poland by its neighbours , and " terras suas Lithuaniae et Russiae Coronae Regni Poloniae perpetuo applicare " , a clause interpreted by historians to mean anything from a personal union between Lithuania and Poland to a complete incorporation of Lithuania into Poland . The agreement at Kreva has been described both as far - sighted and as a desperate gamble . Jogaila was duly baptised at the Wawel Cathedral in Kraków on 15 February 1386 and from then on formally used the name Władysław or Latin versions of it . The marriage took place three days later , and on 4 March 1386 Jogaila was crowned King Władysław by archbishop Bodzanta . He was also to be legally adopted by Jadwiga ' s mother , Elizabeth of Bosnia , so retaining the throne in the event of Jadwiga ' s death . The royal baptism triggered the conversion of most of Jogaila ' s court and noblemen , as well as mass baptisms in Lithuanian rivers , a beginning of the final Christianization of Lithuania . Though the ethnic Lithuanian nobility were the main converts to Catholicism — both paganism and the Orthodox rite remained strong among the peasants — the king ' s conversion and its political implications created lasting repercussions for the history of both Lithuania and Poland . Ruler of Lithuania and Poland . Władysław II Jagiello and Queen Jadwiga reigned as co - monarchs ; and though Jadwiga probably had little real power , she took an active part in Poland ' s political and cultural life . In 1387 , she led two successful military expeditions to Red Ruthenia , recovered lands her father Louis I of Hungary had transferred from Poland to Hungary , and secured the homage of Petru I , Voivode of Moldavia . In 1390 , she also personally opened negotiations with the Teutonic Order . Most political responsibilities , however , fell to Jagiello , with Jadwiga attending to the cultural and charitable activities for which she is still revered . Soon after Jagiello ' s accession to the Polish throne , Jagiello granted Vilnius a city charter like that of Kraków , modeled on the Magdeburg Law ; and Vytautas issued a privilege to a Jewish commune of Trakai on almost the same terms as privileges issued to the Jews of Poland in the reigns of Boleslaus the Pious and Casimir the Great . Władysław ' s policy of unifying the two legal systems was partial and uneven at first but achieved a lasting influence . By the time of the Union of Lublin in 1569 , there was not much difference between the administrative and judicial systems in force in Lithuania and Poland . One effect of Jagiello ' s measures was to be the advancement of Catholics in Lithuania at the expense of Orthodox elements ; in 1387 and 1413 , for example , Lithuanian Catholic boyars were granted special judicial and political privileges denied to the Orthodox boyars . As this process gained momentum , it was accompanied by the rise of both Rus ' and Lithuanian identity in the fifteenth century . Challenges . Jagiello ' s baptism failed to end the crusade of the Teutonic Knights , who claimed his conversion was a sham , perhaps even a heresy , and renewed their incursions on the pretext that pagan s remained in Lithuania . From then on , however , the Order found it harder to sustain the cause of a crusade and faced the growing threat to its existence posed by the Kingdom of Poland and a genuinely Christian Lithuania alliance . Władysław sponsored the creation of the diocese of Vilnius under bishop Andrzej Wasilko , the former confessor of Elisabeth of Hungary . The bishopric , which included Samogitia , then largely controlled by the Teutonic Order , was subordinated to the see of Gniezno and not to that of Teutonic Königsberg . The decision may not have improved Władysław ' s relations with the Order , but it served to introduce closer ties between Lithuania and Poland , enabling the Polish church to freely assist its Lithuanian counterpart . In 1389 , Władysław ' s rule in Lithuania faced a revived challenge from Vytautas , who resented the power given to Skirgaila in Lithuania at the expense of his own patrimony . Vytautas started a civil war in Lithuania , aiming to become the Grand Duke . On 4 September 1390 , the joint forces of Vytautas and the Teutonic Grand Master , Konrad von Wallenrode , laid siege to Vilnius , which was held by Władysław ' s regent Skirgaila with combined Polish , Lithuanian and Ruthenian troops . Although the Knights lifted the siege of the castle after a month , they reduced much of the outer city to ruins . This bloody conflict was eventually brought to a temporary halt in 1392 with the Treaty of Ostrów , by which Władysław handed over the government of Lithuania to his cousin in exchange for peace : Vytautas was to rule Lithuania as the Grand Duke ( " magnus dux " ) until his death , under the overlordship of the Supreme Duke ( " dux supremus " ) in the person of the Polish monarch . Skirgaila was moved from the Duchy of Trakai to become prince of Kiev . Vytautas initially accepted his status but soon began to pursue Lithuania ' s independence from Poland . The protracted period of war between the Lithuanians and the Teutonic Knights was ended on 12 October 1398 by the Treaty of Salynas , named after the islet in the Neman River where it was signed . Lithuania agreed to cede Samogitia and assist the Teutonic Order in a campaign to seize Pskov , while the Order agreed to assist Lithuania in a campaign to seize Novgorod . Shortly afterwards , Vytautas was crowned as a king by local nobles ; but the following year his forces and those of his ally , Khan Tokhtamysh of the White Horde , were crushed by the Timurids at the Battle of the Vorskla River , ending his imperial ambitions in the east and obliging him to submit to Władysław ' s protection once more . King of Poland . On 22 June 1399 , Jadwiga gave birth to a daughter , baptised Elizabeth Bonifacia ; but within a month the mother and daughter died , leaving Władysław sole ruler of the Kingdom of Poland and without an heir nor much legitimacy to rule the kingdom . Jadwiga ' s death undermined Władysław ' s right to the throne ; and as a result old conflicts between the nobility of Lesser Poland , generally sympathetic to Władysław , and the gentry of Greater Poland began to surface . In 1402 , Władysław answered the rumblings against his rule by marrying Anna of Celje , a granddaughter of Casimir III of Poland , a political match which re - legitimised his reign . The Union of Vilnius and Radom of 1401 confirmed Vytautas ' s status as grand duke under Władysław ' s overlordship , while assuring the title of grand duke to the heirs of Władysław rather than those of Vytautas : should Władysław die without heirs , the Lithuanian boyars were to elect a new monarch . Since no heir had yet been produced by either monarch , the act ' s implications were unforeseeable , but it forged bonds between the Polish and Lithuanian nobility and a permanent defensive alliance between the two states , strengthening Lithuania ' s hand for a new war against the Teutonic Order in which Poland officially took no part . While the document left the liberties of the Polish nobles untouched , it granted increased power to the boyars of Lithuania , whose grand dukes had till then been unencumbered by checks and balances of the sort attached to the Polish monarchy . The Union of Vilnius and Radom therefore earned Władysław a measure of support in Lithuania . In late 1401 , the new war against the Order overstretched the resources of the Lithuanians , who found themselves fighting on two fronts after uprisings in the eastern provinces . Another of Władysław ' s brothers , the malcontent Švitrigaila , chose this moment to stir up revolts behind the lines and declare himself grand duke . On 31 January 1402 , he presented himself in Marienburg , where he won the backing of the Knights with concessions similar to those made by Jogaila and Vytautas during earlier leadership contests in the Grand Duchy . Against the Teutonic Order . The war ended in the Treaty of Raciąż on 22 May 1404 . Władysław acceded to the formal cession of Samogitia , and agreed to support the Order ' s designs on Pskov ; in return , Konrad von Jungingen undertook to sell Poland the disputed Dobrzyń Land and the town of Złotoryja , once pawned to the Order by Władysław Opolski , and to support Vytautas in a revived attempt on Novgorod . Both sides had practical reasons for signing the treaty at that point : the Order needed time to fortify its newly acquired lands , the Poles and Lithuanians to deal with territorial challenges in the east and in Silesia . Also in 1404 , Władysław held talks at Vratislav with Wenceslaus IV of Bohemia , who offered to return Silesia to Poland if Władysław supported him in his power struggle within the Holy Roman Empire . Władysław turned the deal down with the agreement of both Polish and Silesian nobles , unwilling to burden himself with new military commitments in the west . Polish – Lithuanian – Teutonic war . In December 1408 , Władysław and Vytautas held strategic talks in Navahrudak Castle , where they decided to foment a Samogitian uprising against Teutonic rule to draw German forces away from Pomerelia . Władysław promised to repay Vytautas for his support by restoring Samogitia to Lithuania in any future peace treaty . The uprising , which began in May 1409 , at first provoked little reaction from the Knights , who had not yet consolidated their rule in Samogitia by building castles ; but by June their diplomats were busy lobbying Władysław ' s court at Oborniki , warning his nobles against Polish involvement in a war between Lithuania and the Order . Władysław , however , bypassed his nobles and informed new Grand Master Ulrich von Jungingen that if the Knights acted to suppress Samogitia , Poland would intervene . This stung the Order into issuing a declaration of war against Poland on 6 August , which Władysław received on 14 August in Nowy Korczyn . The castles guarding the northern border were in such bad condition that the Knights easily captured those at Złotoryja , Dobrzyń and Bobrowniki , the capital of Dobrzyń Land , while German burghers invited them into Bydgoszcz ( German : Bromberg ) . Władysław arrived on the scene in late September , retook Bydgoszcz within a week , and came to terms with the Order on 8 October . During the winter , the two armies prepared for a major confrontation . Władysław installed a strategic supply depot at Płock in Masovia and had a pontoon bridge constructed and transported north down the Vistula . Meanwhile , both sides unleashed diplomatic offensives . The Knights dispatched letters to the monarchs of Europe , preaching their usual crusade against the heathens ; Władysław countered with his own letters to the monarchs , accusing the Order of planning to conquer the whole world . Such appeals successfully recruited many foreign knights to each side . Wenceslas IV of Bohemia signed a defensive treaty with the Poles against the Teutonic Order ; his brother , Sigismund of Luxembourg , allied himself with the Order and declared war against Poland on 12 July , though his Hungarian vassals refused his call to arms . Battle of Grunwald . When the war resumed in June 1410 , Władysław advanced into the Teutonic heartland at the head of an army of about 20 , 000 mounted nobles , 15 , 000 armed commoners , and 2 , 000 professional cavalry mainly hired from Bohemia . After crossing the Vistula over the pontoon bridge at Czerwińsk , his troops met up with those of Vytautas , whose 11 , 000 light cavalry included Ruthenians and Tatars . The Teutonic Order ' s army numbered about 18 , 000 cavalry , mostly Germans and 5 , 000 infantry . On 15 July , at the Battle of Grunwald ( also known as Battle of Tannenberg ) after one of the largest and most ferocious battles of the Middle Ages , the allies won a victory so overwhelming that the Teutonic Order ' s army was virtually annihilated , with most of its key commanders killed in combat , including Grand Master Ulrich von Jungingen and Grand Marshal Friedrich von Wallenrode . Thousands of troops were reported to have been slaughtered on either side . The road to the Teutonic capital Marienburg now lay open , the city undefended ; but for reasons the sources do not explain , Władysław hesitated to pursue his advantage . On 17 July , his army began a laboured advance , arriving at Marienburg only on 25 July , by which time the new Grand Master , Heinrich von Plauen , had organised a defence of the fortress . The apparent half - heartedness of the ensuing siege , called off by Władysław on 19 September , has been ascribed variously to the impregnability of the fortifications , to high casualty figures among the Lithuanians , and to Władysław ' s unwillingness to risk further casualties ; but a lack of sources precludes a definitive explanation . Final years . Dissent . The war ended in 1411 with the Peace of Thorn , in which neither Poland nor Lithuania drove home their negotiating advantage to the full , much to the discontent of the Polish nobles . Poland regained Dobrzyń Land , Lithuania regained Samogitia , and Masovia regained a small territory beyond the Wkra river . Most of the Teutonic Order ' s territory , however , including towns which had surrendered , remained intact . Władysław then proceeded to release many high - ranking Teutonic Knights and officials for apparently modest ransoms . The cumulative expense of the ransoms , however , proved a drain on the Order ' s resources . This failure to exploit the victory to his nobles ' satisfaction provoked growing opposition to Władysław ' s regime after 1411 , further fuelled by the granting of Podolia , disputed between Poland and Lithuania , to Vytautas , and by the king ' s two - year absence in Lithuania . In an effort to outflank his critics , Władysław promoted the leader of the opposing faction , bishop Mikołaj Trąba , to the archbishopric of Gniezno in autumn 1411 and replaced him in Kraków with Wojciech Jastrzębiec , a supporter of Vytautas . He also sought to create more allies in Lithuania . In the Union of Horodło , signed on 2 October 1413 , he decreed that the status of the Grand Duchy of Lithuania was " tied to our Kingdom of Poland permanently and irreversibly " and granted the Catholic nobles of Lithuania privileges equal to those of the Polish szlachta . The act included a clause prohibiting the Polish nobles from electing a monarch without the consent of the Lithuanian nobles , and the Lithuanian nobles from electing a grand duke without the consent of the Polish monarch . Last conflicts . In 1414 , a sporadic new war broke out , known as the " Hunger War " from the Knights ' scorched - earth tactics of burning fields and mills ; but both the Knights and the Lithuanians were too exhausted from the previous war to risk a major battle , and the fighting petered out in the autumn . Hostilities did not flare up again until 1419 , during the Council of Constance , when they were called off at the papal legate ' s insistence . The Council of Constance proved a turning point in the Teutonic crusades , as it did for several European conflicts . Vytautas sent a delegation in 1415 , including the metropolitan of Kiev ; and Samogitian witnesses arrived at Constance at the end of that year to point out their preference for being " baptised with water and not with blood " . The Polish envoys , among them Mikołaj Trąba , Zawisza Czarny , and Paweł Włodkowic , lobbied for an end to the forced conversion of heathens and to the Order ' s aggression against Lithuania and Poland . As a result of the Polish – Lithuanian diplomacy , the council , though scandalised by Włodkowic ' s questioning of the monastic state ' s legitimacy , denied the Order ' s request for a further crusade and instead entrusted the conversion of the Samogitians to Poland – Lithuania . The diplomatic context at Constance included the revolt of the Bohemian Hussite s , who looked upon Poland as an ally in their wars against Sigismund , the emperor elect and new king of Bohemia . In 1421 , the Bohemian Diet declared Sigismund deposed and formally offered the crown to Władysław on condition he accept the religious principles of the Four Articles of Prague , which he was not prepared to do . After Władysław ' s refusal , Vytautas was postulated ( elected in absentia ) as Bohemian king , but he assured the pope that he opposed the heretics . Between 1422 and 1428 , Władysław ' s nephew , Sigismund Korybut , attempted a regency in war - torn Bohemia , with little success . Vytautas accepted Sigismund ' s offer of a royal crown in 1429 — apparently with Władysław ' s blessing — but Polish forces intercepted the crown in transit and the coronation was cancelled . In 1422 , Władysław fought another war , known as the Gollub War , against the Teutonic Order , defeating them in under two months before the Order ' s imperial reinforcements had time to arrive . The resulting Treaty of Melno ended the Knights ' claims to Samogitia once and for all and defined a permanent border between Prussia and Lithuania . Lithuania was given the province of Samogitia , with the port of Palanga , but the city of Klaipėda was left to the Order . This border remained largely unchanged for roughly 500 years , until 1920 . The terms of this treaty have , however , been seen as turning a Polish victory into defeat , as a result of Władysław ' s renunciation of Polish claims to Pomerania , Pomerelia , and Chełmno Land , for which he received only the town of Nieszawa in return . The Treaty of Melno closed a chapter in the Knights ' wars with Lithuania but did little to settle their long - term issues with Poland . Further sporadic warfare broke out between Poland and the Knights between 1431 and 1435 . Cracks in the cooperation between Poland and Lithuania after the death of Vytautas in 1430 had offered the Knights a revived opportunity for interference in Poland . Władysław supported his brother Švitrigaila as grand duke of Lithuania , but when Švitrigaila , with the support of the Teutonic Order and dissatisfied Rus ' nobles , rebelled against Polish overlordship in Lithuania , the Poles , under the leadership of Bishop Zbigniew Oleśnicki of Kraków , occupied Podolia , which Władysław had awarded to Lithuania in 1411 , and Volhynia . In 1432 , a pro - Polish party in Lithuania elected Vytautas ' s brother Žygimantas as grand duke , leading to an armed struggle over the Lithuanian succession which stuttered on for years after Władysław ' s death . Succession . Władysław ' s second wife , Anna of Celje , had died in 1416 , leaving a daughter , Jadwiga . In 1417 , Władysław married Elisabeth of Pilica , who died in 1420 without bearing him a child , and two years later , Sophia of Halshany , who bore him two surviving sons . The death in 1431 of Princess Jadwiga , the last heir of Piast blood , released Władysław to make his sons by Sophia of Halshany his heirs , though he had to sweeten the Polish nobles with concessions to ensure their agreement , since the monarchy was elective . Władysław finally died in 1434 , leaving Poland to his elder son , Władysław III , and Lithuania to his younger , Casimir , both still minors at the time . The Lithuanian inheritance , however , could not be taken for granted . His death in 1434 ended the personal union between the two realms , and it was not clear what would take its place .