Battle on the Marchfeld The Battle on the Marchfeld ( " i . e . Morava Field " ; Czech : " Bitva na Moravském poli " ) at Dürnkrut and Jedenspeigen took place on 26 August 1278 and was a decisive event for the history of Central Europe for the following centuries . The opponents were a Bohemian ( Czech ) army led by the Přemyslid king Ottokar II of Bohemia and the Imperial army under the German king Rudolph I of Habsburg in alliance with King Ladislaus IV of Hungary . Although both sides had in their units also infantry , the battle itself was primarily a great collision of heavy knight s cavalry , though the Cuman horse archers in the Hungarian army played a vital role . The battle was finally won by an ambush attack of the united Imperial - Hungarian forces , which was in those times considered dishonourable and against the rules of knighthood . Background . The deposition of Emperor Frederick II of Hohenstaufen by Pope Innocent IV in 1245 created a grave crisis for the Holy Roman Empire , as in the following decades several nobles were elected as " Rex Romanorum " and Emperor - to - be , none of whom were able to gain actual governing power upon the Emperor ' s death in 1250 . That same year , Ottokar II , son of king Wenceslaus I of Bohemia , moved into the princeless Duchies of Austria and Styria . The last Babenberg duke Frederick II of Austria had been killed at the 1246 Battle of the Leitha River , in a border conflict he had picked with King Béla IV of Hungary . Ottokar II gained the support of the local nobility and was proclaimed Austrian and Styrian duke by the estates one year later . In 1253 Ottokar II became Bohemian king upon the death of his father ; the concentration of power on the western Hungarian border was viewed with suspicion by King Béla IV , who campaigned Austria and Styria but was finally defeated at the 1260 Battle of Kressenbrunn . In 1268 Ottokar signed a contract of inheritance with Ulrich III , the last Carinthian duke of the House of Sponheim , and thus acquired Carinthia including the March of Carniola and the Windic March one year later . At the height of his power he aimed at the Imperial crown , but the Princes - Electors ( " Kurfürsten " ) , distrustful of his steep rise , elected the " poor Swabian count " Rudolph of Habsburg King of the Romans on September 29 , 1273 . Preparations . As the election had taken place in his absence , Ottokar did not acknowledge Rudolph as King . Rudolph himself had promised to regain the " alienated " territories which had to be conferred by the Imperial power with consent of the Prince - electors . He claimed the Austrian and Carinthian territories for the Empire and summoned Ottokar to the 1275 " Reichstag " at Würzburg . By not appearing before the Diet , Ottokar set the events of his demise in motion . He was placed under the Imperial ban and had all his territorial rights revoked , including even his Bohemian inheritance . Meanwhile , Rudolph was gathering allies and preparing for battle . He achieved two of these alliances through the classic Habsburg style – marriage . First , he married his son Albert to Elisabeth of Gorizia - Tyrol . In return , her father Count Meinhard II of Gorizia - Tyrol received the Duchy of Carinthia as a fief . Second , he established an — unstable — alliance with Duke Henry I of Lower Bavaria by offering him his daughter Katharina as wife for his son Otto in addition to the region of present - day Upper Austria as a pledge for her dowry . He also concluded an alliance with King Ladislaus IV of Hungary , who intended to settle old scores with Ottokar . Rudolph , so strengthened , besieged Ottokar at the Austrian capital Vienna in 1276 . Ottokar was forced to surrender and to renounce all his acquisitions , receiving only Bohemia and Moravia as a fief from King Rudolph . Heavily deprived by this , he was determined to regain his territories and contracted an alliance with the Ascanian Margraves of Brandenburg and the Polish princes . In 1278 he campaigned Austria , supported by Duke Henry I of Lower Bavaria , who had switched sides . Ottokar first laid siege to the towns of Drosendorf and Laa an der Thaya near the Austrian border , while Rudolph decided to leave Vienna and to face the Bohemian army in an open pitched battle in the Morava basin north of the capital , where the Cuman cavalry of King Ladislaus could easily join his forces . Battle . Surprised by Rudolph ' s maneuver , Ottokar quickly abandoned the siege at Laa , marched southwards , and on August 26 met the united Imperial and Hungarian forces near Dürnkrut . When he arrived his enemies had already taken the opportunity to explore the topography of the future battleground . From the early morning , the left wing of the advancing Bohemian troops were embroiled in impetuous attacks by the Cuman forces , which the heavy - armed knights could not ward off . Nevertheless as the main armies collided and the battle wore on , Ottokar ' s outnumbering cavalry seemed to gain the upper hand , when even Rudolph ' s horse was stabbed under him and the 60 - year - old narrowly escaped with his life , rescued by his liensmen . After three hours of continued fighting on a hot summer day , Ottokar ' s knights in their heavy armour were exhausted , many of them suffered from circulatory failure and were not able to move . At noon Rudolph ordered a fresh heavy cavalry regiment he had concealed behind nearby hills and woods to attack the right flank of Ottokar ' s troops . Such ambushes were indeed commonly regarded as dishonourable in warfare and Rudolph ' s commander Ulrich von Kapellen apologized to his own men in advance . Nevertheless the attack prevailed in splitting and stampeding the Bohemian troops . Ottokar realized the surprise attack and tried to lead a remaining reserve contingent in the rear of von Kapellen ' s troops , a maneuver that was misinterpreted as a rout by the Bohemian forces . The following collapse resulted in a complete victory of Rudolph and his allies . Ottokar ' s camp was plundered , and he himself was found slain on the battlefield . Aftermath . Rudolph , to demonstrate his victory , had Ottokar ' s body displayed in Vienna . The " poor count " from Swabian Habsburg Castle assured his possession of the Duchies of Austria and Styria , the heartland and foundation of the rise of the House of Habsburg . At the 1282 Diet of Augsburg , he installed his sons Albert and Rudolf II as Austrian dukes ; their descendants held the ducal dignity until 1918 . However in Bohemia , Rudolph acted cautiously and reached an agreement with the nobility and Ottokar ' s widow Kunigunda of Slavonia on the succession of her son Wenceslaus II to the throne . On the same occasion he reconciled with the Brandenburg margraves , ceding them the guardianship over the minor heir apparent . King Ladislaus IV exerted himself in the christianization of the Cuman warriors , before he was assassinated in 1290 . Ottokar ' s son , the young king Wenceslaus II of Bohemia , turned out to be a capable ruler . In 1291 he acquired the Polish Seniorate Province at Kraków and was crowned King of Poland in 1300 . He was even able to secure the Hungarian crown for his son Wenceslaus III , still a minor , who nevertheless was murdered in 1306 , one year after his father ' s death , whereby the Přemyslid dynasty became extinct . Battle on the Marchfeld in art and popular culture . The battle was depicted in art especially during the rise of nationalism in the 19th century , when it was viewed as the example of an tradional cooperation between Habsburg dynasty ( Austria ) and Kingdom of Hungary from one side and the tradional tension between Habsburg dynasty and Bohemia from the Czech side . The tragedy " König Ottokars Glück und Ende " written by Franz Grillparzer in 1823 is based on the rise and fall of king Ottokar II . This drama was originally inspired by the life of Napoleon , though Grillparzer , fearing Metternich ' s censorship , chose to write the play about Ottokar , in whose story he found many parallels . It nevertheless was immediately forbidden and could not be performed until 1825 . Grillparzer perpetuated the legend of Ottokar ' s wife Margaret of Babenberg unsuccessfully trying to reconcile the opponents on the eve of the battle . In fact , Margaret had died already in 1266 . The opera " The Brandenburgers in Bohemia " composed by Czech composer Bedřich Smetana in 1863 was inspired by this battle and following events as well .