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.