Whiggism , in North America sometimes spelled Whigism , is a historical political philosophy that grew out of the Parliamentarian faction in the Wars of the Three Kingdoms (1639–1651). The Whigs' key policy positions were the supremacy of Parliament (as opposed to that of the king), tolerance of Protestant dissenters , and opposition to a " Papist " ( Roman Catholic ) on the throne, especially James II or one of his descendants.  After the huge success (from the Whig point of view) of the Glorious Revolution of 1688–1689, Whiggism dominated English and British politics until about 1760, although in practice it splintered into different factions. After 1760 the Whigs lost power, apart from sharing it in some short-lived coalition governments , but Whiggism fashioned itself into a generalized belief system that emphasized innovation and liberty and was strongly held by about half of the leading families in England and Scotland, as well as most merchants, Dissenters, and the middle classes. The opposing Tory position was held by the other great families, the Church of England , most of the landed gentry , and officers of the army and the navy.
Whiggism originally referred to the Whigs of the British Isles , but the name of "Old Whigs" was largely adopted by the American Patriots in the Thirteen Colonies. Following independence, American Whiggism became known as republicanism. The term "Old Whigs" was also used in Britain for those Whigs who opposed Robert Walpole as part of the Country Party.