Aragon

The House of Barcelona descended from Wilfred the Hairy, count of Barcelona from 878, whose heirs built the county into the leading Catalan power. In 1137 Count Ramon Berenguer IV married Petronilla, heiress of Aragon, their son Alfonso II becoming first king of the united Crown of Aragon in 1162.

Under James the Conqueror it took Mallorca in 1229 and Valencia in 1238; a cadet kingdom of Mallorca lasted until Peter IV reunited it in the 1340s. The Sicilian Vespers of 1282 carried Peter III to Sicily, where a younger branch ruled until 1409, while the family's Occitan claims in Provence had passed to the Angevins in 1246. In 1337 Peter IV ruled a Mediterranean power whose fleets and Catalan Company brought Athens under the family's cadets.

The main line ended with Martin the Humanist in 1410. After an interregnum, the 1412 Compromise of Caspe gave the crown to Ferdinand of Antequera of the Castilian House of Trastámara, though Barcelona's Urgell branch contested it.