Alaejos is a municipality located in the province of Valladolid, Castile and León, Spain. According to the 2011 census, the municipality has a population of 1,467 inhabitants. Even though the origins of the town remain uncertain, it is known that it was part of the old province of Toro. Its name around the 12th and 13th century was Falafeios. One theory says that it might have been founded by the Castilian monarchs as a hamlet in the reconquered territories during the Reconquista.