The Lordship of Prilep was one of the provinces of the Serbian Empire, held by Vukašin Mrnjavčević, the co-ruler of Serbia alongside child-less Uroš the Weak (r. 1355-1371). Lord Vukašin died at the Battle of Maritsa and Emperor Uroš died later in 1371, so Prilep was obtained by Marko Mrnjavčević, the son of Lord Vukašin. Since Marko is referred to as King in South Slavic folklore, (he had the personal title of young king given by his father), the realm is in some sources called the Kingdom of Prilep (Macedonian and Bulgarian: Прилепско кралство, Prilepsko kralstvo). as the seat of the province was at Prilep, present-day Republic of Macedonia.
States in the Central Balkans that emerged after dissolution of Serbian Empire in the 14th century
The lands were held by Serbian feudal lord Vukašin Mrnjavčević, who was crowned the king of the Serbs and Greeks in 1365 as the co-ruler of last Serbian emperor Uroš. After the death of both Uroš and Vukašin in 1371, Vukašin's son Marko Mrnjavčević, known as King Marko, became the sole legal ruler of the Serbian Empire but his power was contested by other Serbian feudal lords who gained control over other regions leaving Marko only with the areas in western Macedonia. So, after his father's death, Marko became effective ruler of the Kingdom of Prilep.