In this article, we present one of the most mythicised episodes in the history of Catalonia, first the cooperation and later the clash between the Catalan Company, led by the intrepid Roger de Flor (also known as Roger von Blume and Rutger Blume), and the Byzantine emperor Andronikos II Palaiologos and his son and co-regent Michael IX. We also discuss their settlement in the duchy of Athens in 1311, which later expanded to the duchy of Neopatria, where the Catalans remained a constant presence for more than 70 years. Special attention is paid to the meagre archaeological remains (especially towers and castles) still surviving from that phenomenal adventure in continental Greece, the negative memory this episode has left in Greek folklore, and the conversion of the Almogavar adventurer into a national myth in both Greece and Catalonia, albeit from diametrically opposed positions.