Serbian nobility conflict (1369)

The Serbian nobility conflict in 1369 was a conflict between two major opposing factions of the Serbian nobility, one supporting magnate Nikola Altomanović, and one supporting the Mrnjavčević family in Macedonia and Greece. In 1369, a battle was fought between the two sides at the Kosovo field, ending in the decisive victory of King Vukašin, confirming his supremacy, which would last until 1371 battle of Maritsa.

Source: Wikipedia — Serbian nobility conflict (1369) (CC BY-SA 4.0)