The Cathars had their main centre at Albi and so they were known also as "Albigens" after the city. The Cathar movement was a branch of Christianity which was persecuted in the Middle Ages. Because of this, the city was almost completely destroyed in a crusade between 1209 and 1229. Since 1678, the city is the seat of an archbishop. Since 1790, it is the capital city of the Tarn department.