How Mercenaries Beat Empires

TL;DR

The Great Catalan Company — Aragonese mercenaries hired to defend Byzantium — mutinied, conquered Athens, and ruled Greece for 80 years after their employer tried to assassinate their leader.

Key Points

• 1.Origins & makeup: The Catalan Company was formed from unemployed Almogavar light infantry after the War of the Sicilian Vespers (1282–1302). Led by Roger de Flor, they numbered between 1,000–8,000 men and excelled at shock tactics, psychological warfare, and striking flint on swords while screaming "Light Iron! It's time to kill!"
• 2.Hired by Byzantium (1303): Emperor Andronikos II, reeling from defeat at the Battle of Bapheos against Osman I, hired the Company to fight Turkic Beyliks in Anatolia. Roger de Flor was married to the Emperor's niece and given the rank of Megas Doux.
• 3.Betrayal at Adrianople (1305): After the Catalans successfully lifted the siege of Philadelphia and won multiple battles, Byzantine co-emperor Michael IX ambushed Roger de Flor at a banquet, killing him along with 100 cavalry and 1,000 infantry.
• 4.Revenge and survival: The surviving Catalans escaped to Gallipoli, defeated the Byzantines at the Battle of Apros (1305), recruited defecting Turkic mercenaries, and raided Thrace and Macedonia for two years in retaliation.
• 5.Conquest of Athens (1311): Hired by the Duke of Athens, Walter V of Brienne, the Company was never paid. They killed the Duke at the Battle of Halmyros and seized the Duchy of Athens and Thebes outright.
• 6.80-year rule of Greece: The Company placed the Duchy under Aragonese-Sicilian protection, made Catalan an official language, imposed the Customs of Barcelona as law, and expanded control into Thessaly — ruling as the de facto aristocracy until the 1380s.
• 7.Downfall (1388–1390): Internal noble feuds and Florentine mercenaries calling in the Navarrese Company eroded Catalan power. Florence took Athens in 1388 and Neopatras fell in 1390, ending Catalan rule. "Catalan" remained a Greek insult for a violent person into the 20th century.