The house ruled a province from its base at Prilep (in modern North Macedonia) from 1366 to 1395.

After Uroš' death, the Serbian Empire crumbled, as the nobility could not agree on its rightful successor.

Vukašin's son, Marko Kraljević, ruled his hereditary lands as titular King of Serbs and Greeks.

The family's progenitor, after whom historiography names it, was Mrnjava, a financial chancellor (kaznac, chamberlain) who served King Stefan Uroš I and his wife, Queen Helen of Anjou at the court at Trebinje (in Travunia).

[1] Ragusan historian Mavro Orbin (1563–1610) wrote that the family hailed from Hum, and that the poor Mrnjava and his three sons, who later lived in Blagaj,[2] quickly rose to prominence under King Stefan Dušan.