Sancha of Castile, Queen of Aragon

Sancha of Castile (21 September 1154/5 – 9 November 1208) was the only surviving child of King Alfonso VII of León and Castile by his second wife, Richeza of Poland. Alfonso VII had also given the same name, Sancha, to his daughter by his first wife, Berengaria of Barcelona. This half-sister married King Sancho VI of Navarre in 1153.

Sancha was actively involved in political affairs, particularly in disputes over territorial control, and is recorded as participating in royal governance alongside her her husband Alfonso II. She is also notable for her religious patronage, most prominently as the founder of the Royal Monastery of Santa María de Sigena, which became an important religious and dynastic center.