Joshua Clayton was born on July 20, 1744 in Cecil County, Maryland, United States. He was a descendant of Joshua Clayton who accompanied William Penn on one of his visits to this country. The younger Joshua’s father, James Clayton, settled with his wife Grace in Cecil County, Maryland, where their son was born. At one time the father was engaged in milling in Kent County, Delaware.
Joshua was a student at the University of Pennsylvania from 1757 to 1762.
Clayton practised his medical profession quietly until he was interrupted by the Revolution. His Quaker antecedents did not hinder him from taking part in the war and on January 6, 1776, he was elected second major of Bohemia Battalion, a body of militia recruited from the inhabitants of Bohemia Manor where he was then living. The battalion was later incorporated into the Continental Army, Clayton being commissioned colonel by Washington and placed on his staff. His active participation in the war seems to have been limited to the battle of Brandywine.
After the war his career as a statesman began with his election to the Delaware House of Assembly in 1785 and again in 1787. A year previous to the last election he had been made state treasurer. His rise to position was rapid and on May 30, 1789, he was elected president of Delaware. He held office in this capacity until 1792, when a new constitution was adopted and the title of president changed to governor. Under this new constitution Clayton sought a second term and in the fall of 1792 was victorious by a majority of 307 over his opponent, Thomas Montgomery. At the end of his second term, January 13, 1796, he resumed his practise at Bohemia Manor in Delaware.
A great part of his influence must have resulted from his immense land holdings, some of which were acquired as early as 1791. It is estimated that he and Richard Bassett, his wife’s foster father, owned about 20, 000 acres in Bohemia Manor. Clayton was again pressed into public service with his election as United States senator on January 19, 1798. While in Philadelphia in the summer of that year he was in frequent consultation with Dr. Rush and other physicians on the yellow-fever epidemic then prevalent. He contracted the disease and retired at once to his estate, where he died.
Joshua Clayton as a medical man was known for his discovery of a substitute for Peruvian Bark which became very scarce during the Revolution. This consisted of a mixture of poplar bark, the bark of dogwood root, and the bark of white oak, and was said to be efficacious as a remedy for gangrene and mortifications. During his tenure as a governor, construction on a meeting place began in Dover, a welfare act was passed and several acres of land were passed by the state to the U. S. government.
Joshua Clayton was member of the Federalist Party.
Clayton married Rachael McCleary, an adopted daughter of Richard Bassett, former governor of Delaware.
