The village name is Anglo Saxon and means Hill overgrown with ash trees. In the Domesday Book of 1086 the village was listed as the property of the Grenville family; it was called Assedune. The original name refers to the fact that in Saxon times this area was completely forested, and served as hunting land for the king.
In recent times the manor of Ashendon passed into the hands of the Marquis of Buckingham.
Included in with the parish of Ashendon are the hamletss of Upper Pollicott and Lower Pollicott. The names of these hamlets derive from the Anglo Saxon Pol's Cottage.