Castile and León is an autonomous community in north-western Spain. It was so constituted in 1983 and it comprises the historical regions of León and Old Castile . It is the largest autonomous community in Spain covering an area of 94 223 square kilometres (36 380 sq mi) with an official population of around 2.5 million (2005). The organic law of Castile and León under the Spanish Constitution of 1978 is the region's Statute of Autonomy.