The first political factions, cohering around a basic, if fluid, set of principles emerged from the Exclusion Crisis and Glorious Revolution in late-17th-century England. The Whigs supported Protestant constitutional monarchy against absolute rule and the Tories, originating in the Royalist (or "Cavalier") faction of the English Civil War, were conservative royalist supporters of a strong monarchy as a counterbalance to the republican tendencies of Whigs, who were the dominant political faction for most of the first half of the 18th century; they supported the Hanoverian succession of 1715 against the Jacobite supporters of the deposed Roman Catholic Stuart dynasty and were able to purge Tory politicians from important government positions after the failed Jacobite rising of 1715. The leader of the Whigs was Robert Walpole, who maintained control of the government in the period 1721–1742; his protégé was Henry Pelham (1743–1754).