Colmenar de Oreja is a town and municipality of the Las Vegas comarca, in the Community of Madrid, Spain. It was subject to a seven-month siege in 1139.

Alfonso VII, called the Emperor, became the King of Galicia in 1111 and King of León and Castile in 1126. Alfonso, born Alfonso Raimúndez, first used the title Emperor of All Spain, alongside his mother Urraca, once she vested him with the direct rule of Toledo in 1116. Alfonso later held another investiture in 1135 in a grand ceremony reasserting his claims to the imperial title. He was the son of Urraca of León and Raymond of Burgundy, the first of the House of Ivrea to rule in the Iberian peninsula.