From the beginning of his reign, Alfonso employed Jewish, Christian and Muslim scholars at his court, primarily for the purpose of translating books from Arabic and Hebrew into Latin and Castilian, although he always insisted in supervising personally the translations. This group of scholars formed his royal scriptorium, continuing the tradition of the twelfth-century Escuela de Traductores de Toledo (Toledo School of Translators). Their final output promoted Castilian as a learning language both in science and literature, and established the foundations of the new Spanish language. This evolved version of the Castilian language also acquired significant relevance in the royal chancery, where it came to replace Latin, which until then had been the language commonly used for royal diplomacy in Castile and León.