Cornwell was listed in the Domesday Book of 1096 as "Cornewelle" in the ancient hundred of Shipton.[2]
The manor house dates from the 16th or 17th century, with a dining room and library panelled in about 1640[3] and 17th century stables and dovecote.[4] It was the home of Sir Thomas Penyston, 1st Baronet and his family occupied the house until the 19th century. A new front was built onto the house in about 1750, and the drawing room has a fireplace in the style of Robert Adam.[3] In 1939 the architect Clough Williams-Ellis, who had designed Portmeirion in north Wales, restored the house, added a ballroom and laid out the gardens.[5] The house is a Grade II* listed building.[6]
Some of the cottages in the village are 17th century.[4] In 1939 Williams-Ellis remodelled all the cottages in Cornwell and remodelled the former village school in neo-Georgian style as the village hall.[4]