With James Madison and Thomas Jefferson, Mason carried through the Virginia legislature measures disestablishing the Episcopal Church and protecting all forms of worship. In politics he was a radical republican, who believed that local government should be kept strong and central government weak; his democratic theories had much influence in Virginia and other southern and western states.
He was attorney-general of Pennsylvania in 1811, comptroller of the treasury of the United States in 1811-14, attorneygeneral in the cabinet of President James Madison in 1814-17, acting secretary of state from March to September 1817, minister to Great Britain in 1817-25, secretary of the treasury in the cabinet of President J.
Of his Republic (Chicago, 1887); John Quincy Adams, The Lives of James Madison and James Monroe (Buffalo, 1850); B.
The success of the Baptists of Virginia in securing step by step the abolition of everything that savoured of religious oppression, involving at last the disestablishment and the disendowment of the Episcopal Church, was due in part to the fact that Virginia Baptists were among the foremost advocates of American independence, while the Episcopal clergy were loyalists and had made themselves obnoxious to the people by using the authority of Great Britain in extorting their tithes from unwilling parishioners, and that they secured the co-operation of free-thinking statesmen like Thomas Jefferson and James Madison and, in most measures, that of the Presbyterians.