The Marquesado de Santillana is a noble title in Spain, established in the 15th century. It was granted to the powerful House of Mendoza, a prominent family in Spanish history. The title is named after the town of Santillana del Mar in the region of Cantabria. The marquisate has a rich history, often associated with the cultural and political developments of the time. The title has been held by various members of the Mendoza family, contributing to their influence in Spanish nobility. Today, the Marquesado de Santillana remains a symbol of historical significance in Spain.