John Mayhew II ( - 1337 PD) was the Protector of Grayson at the beginning of the Civil War.

In the mid 12th Century PD, the Steadholders Simonds, Oswald, and Bancroft led the Faithful in a coup attempt which resulted in the death of John II and the other fifty-three current Steadholders of Grayson as well as their heirs.

However, they failed to kill the Protector's son and heir, Benjamin; the coup failed to secure complete control over the planet, and a brutal civil war ensued after which Benjamin the Great had avanged his father, rebuilt Grayson and become the greatest and most reverred Protector of all time. (HH2, HH5)