The Alberti family was a major political family in Florence. The Alberti originated from the castle of Catenaia in Valdarno Casentinese, whence the presence of two chains (Italian: catena) in their coat of arms. They became established in Florence during the 13th century with judge Rustico Alberti and divided into different lines, who owned several houses and towers near the modern Ponte alle Grazie. Due to their Guelph allegiance, they were exiled after the Battle of Montaperti, but returned after Manfred of Sicily's defeat in the battle of Benevento (1266). They subsequently sided for the Black Guelph faction, and established a flourishing trade company with agencies at Bologna, Genoa, Venice, Barcelona, Paris, Ghent, Brussels, Bruges and London, as well as in Syria and Greece.