In the Middle Ages, the kings of Castile and Leon issued solemn documents, the "rodados" privileges, as formulas for bestowing grants to subjects and institutions, which are characterized by their beauty, solemnity, durability, elegance and hierarchy, and for being instruments of guarantee of rights, propaganda and power. The name "rodados" comes from the characteristic "rueda" or signum regis circular that is represented in the document; and the beauty of its progressive development as art of illumination.