The village name is of Twelfth century origin and means 'king's island', referring to a piece of dry land that belonged to the king in the marshes that were once common in this part of the country. In 1174 the village was called Eya, meaning 'island', though by 1192 it had gained its more modern name of Kingesie. This leads historians to believe that the village is named after King Richard I of England.
As is typical with villages on county borders it has changed counties several times in its history. Officially Kingsey is in Buckinghamshire, though it is considered by some, even today, to be a part of Oxfordshire.
Historically people from this village and those surrounding it were known by the derogatory term 'wetfeet', because of the high water table of the area leading to the ground being so waterlogged.