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]). Thomas John Claggett was the first to use the double "g" in spelling his family's name.