Born in London, England, the son of Ezekiel King, he was related to the family of Edward Hyde, 1st Earl of Clarendon.
In 1702, having moved to Ireland, he was made Judge of the Admiralty, Commissioner of the Prizes, Keeper of the Records in Birmingham's Tower, and Vicar-General to Narcissus Marsh, the primate.
Both men were severely criticised by their political opponents for neglecting their official duties; it was said that they had no ambition but to live out their days in rural retirement.
In 1710, he became a supporter of the High Church party, on the side of Henry Sacheverell, and was supposed to have had some part in setting up The Examiner.
[3] He had already made some translations from the French language and written some humorous and satirical pieces, and in 1694, Molesworth published his Account of Denmark, in which he treated the Danes and their monarch with great contempt.