Ferdinand Farmer was born with the Swabian name of Steinmeyer, but changed his name to Farmer after coming to America. As a young man he spent three years studying medicine before becoming a follower of Loyola in 1743.
He was sent as a missionary to German Catholic settlers in Pennsylvania, arriving in Lancaster in 1752. Six years later he was sent to the German parish of St. Joseph in Philadelphia, a parish which at that time included not only Philadelphia, but also New York City and most of New Jersey. As a result, Rev. Farmer spent a good deal of time on the road.
During the Revolutionary War, Rev. Farmer steadfastly refused to become a chaplain of a British regiment of Roman Catholics, and instead was the first to sign a 1783 address to Washington by the clergy, attorneys, and physicians of Philadelphia.
He was a learned astronomer and mathematician and a member of the American Philosophical Society. As the senior minister of the Roman Catholic Church in Philadelphia, Rev. Farmer served as an ex officio trustee of the University of the State of Pennsylvania (now the University of Pennsylvania) from 1779 until his death in 1786.