Benjamin Allworthy is the earliest mentioned holder of the post of Chrestomanci in the series of that name. He served some two hundred years previous to the events in the last book of the series, The Pinhoe Egg. There are few descriptions of him in the books of the series, but it appears to have been under his service as Chrestomanci that a local man, Jed Farleigh, was hired as gamekeeper. Evidently several of the mages who worked under Allworthy hunted game at the time.
Farleigh, who became Gaffer of his clan, managed to retain the post of gamekeeper at the Castle for the whole of those 200 years, even having his salary increased.