 He was the great grandson of Captain Thomas Clagett who emigrated from England and settled on St. Leonard's Creek in Calvert County, Maryland in 1671.Captain Clagett at one time owned more than in central and northeastern Maryland in Calvert, Prince George's, Baltimore and Kent Counties.He was a Justice and Coroner of Calvert County and an opponent of Maryland Governor John Coode, (1648-1709), who was a leader of Coode's Rebellion (also known as the "Protestant Rebellion" in 1689 against the Lord Proprietor of the Province of Maryland, the third Lord Baltimore, Charles Calvert, [1637-1715]).