The name of the town comes from Latin "castrum", and means "fortified place". Castres grew up round the Benedictine abbey of Saint Benoît, which is believed to have been founded in AD 647, possibly on the site of an old Roman fort ("castrum"). Castres became an important stop on the international pilgrimage routes to Santiago de Compostela in Spain because its abbey-church, built in the 9th century, was keeping the relics of Saint Vincent, the renowned martyr of Spain. It was a place of some importance as early as the 12th century, and ranked as the second town of the Albigeois behind Albi. Despite the decline of its abbey, which in 1074 came under the authority of Saint Victor abbey in Marseille, Castres was granted a liberal charter in the 12th century by the famous Trencavel family, viscounts of Albi. Resulting from the charter, Castres was ruled by a college of consuls.