 The irrigated Ebro valley contrasts with mountainous areas of low rainfall, marked in the past by rural poverty, a stronghold of anarcho-syndicalism in the earlier 20th century and, in the Maestrazgo, of Carlism in the 19th century.Aragon, like Catalonia, maintained much of its independence under the Crown of Castile, up to the point of a revolt in 1591-1592 over their regional rights and independence.The region retained significant Arab influence after the expulsion, particularly in the Ebro valley to the south, although leaving less trace architecturally than in Valencia.