Glassthorpe was mentioned in the
Domesday Book of 1086 as Glassthorpehill, and had a recorded population of six people, paying 1.8 geld units in tax at the time. The feudal lord in 1088 was
William of Keynes. It is mentioned in the
Nomina Villarum of 1316 and was still inhabited in 1371. In 1515 it was acquired by
John Spencer of the prominent
Spencer family of aristocrats of
Althorp. In 1547 "Classthorpe Pasture" was documented to have 200 sheep. By the early 18th century Glassthorpe had been "long depopulated", and only contained a single shepherd's house. ==References==