Pinco?

1066

According to one scholar, “The earliest Pynchon on record is one Pinco, ‘sworn brother in war” to Endo, who came to England from Normandy with William the Conqueror,” who led the invasion of England out of the St-Malo region (Normandy).

This Pinchon family still exists, mainly in Brittany and Normandy, under the names of 'Pinçon' or 'Pinchon'.

There is a 300 m (1,200 ft) hill in the Calvados region called Mont Pinçon, taken by the British after heavy fights on August 6, 1944. The name is not unusual in France: in Louis-Ferdinand Céline's 'Journey to the End of the Night' (1932) figures a rather nasty army officer called 'Pinçon'.

http://www.vheissu.info/bio/eng_tijdlijn.htm

Info about the "Pinchin" Coat of Arms

http://www.houseofnames.com/xq/asp.c/qx/pinchin-coat-arms.htm#products