John was a Power Loom Weaver from England. He was a teamster in the John A. Hunt company and was among the small group of men who remained behind at Devil's Gate until spring to guard the personal belongings of the emigrants who had been rescued that winter.
In some sources his surname is spelled "Whittaker," but it is spelled "Whitaker" on the original Hunt Company roster, in a newspaper article preserved in the Journal History at the Church History Library in Salt Lake City. It is also spelled "Whitaker" in the 1880 Utah census, as well as various death records and his christening record.