around Ser. Later he became strong enough to disobey Uroš. By 1369, as Uroš was childless, Vukašin designated his eldest son Prince Marko as heir to the throne, with the title of "young king". In 1370 he contributed to the monasteries of Mount Athos and prepared a war against the Ottoman Empire, which his brother supported. Vukašin was to attack Trebinje in June 1371 but it was never carried out. In September 1371, he established a coalition with his brother against the Ottomans and advanced. The Serbian army of the coalition numbering ca. 70,000 men met the Ottoman army led by beylerbey of Rumeli Lala Şâhin Paşa at Battle of Maritsa on 26 September 1371 where superior Ottoman tactics won over outnumbering coalition army. The Ottomans attacked the Serbian Army while they rested and Vukašin's forces were routed and himself killed during the battle. Family With his wife Jelena (Old Cyrillic: Алѣна), Vukašin had at least five children: Marko Mrnjavčević Andrijaš Mrnjavčević Dmitar Mrnjavčević Ivaniš Mrnjavčević Olivera Mrnjavčević Jelisanta Jelena, married to Rajko Moneta In popular culture Brian Aldiss - published an alternative-history fantasy story "The Day Of The Doomed King" about King Vukašin. See also House of Mrnjavčević Serbian nobility conflict (1369) Serbian epic poetry References Sources 14th-century Serbian nobility People of the Serbian Empire Yukasin Despots of the Serbian Empire History of Kosovo Medieval Macedonia People from Livno Characters in Serbian epic poetry 1320s births 1371 deaths Medieval Serbian magnates Medieval Serbian military leaders 14th-century soldiers