of the defeated Tory Party sympathised with the Jacobites, who sought to replace George with Anne's Catholic half-brother, James Francis Edward Stuart (called "James III and VIII" by his supporters and "the Pretender" by his opponents). Some disgruntled Tories sided with a Jacobite rebellion, which became known as "The Fifteen". James's supporters, led by Lord Mar, an embittered Scottish nobleman who had previously served as a secretary of state, instigated rebellion in Scotland where support for Jacobitism was stronger than in England. "The Fifteen", however, was a dismal failure; Lord Mar's battle plans were poor, and James arrived late with too little money and too few arms. By the end of the year the rebellion had all but collapsed. In February 1716, facing defeat, James and Lord Mar fled to France. After the rebellion was defeated, although there were some executions and forfeitures, George acted to moderate the Government's response, showed leniency, and spent the income from the forfeited estates on schools for Scotland and paying off part of the national debt. George's distrust of the Tories aided the passing of power to the Whigs. Whig dominance grew to be so great under George that the Tories did not return to power for another half-century. After the election, the Whig-dominated Parliament passed the Septennial Act 1715, which extended the maximum duration of Parliament to seven years (although it could be dissolved earlier by the Sovereign). Thus Whigs already in power could remain in such a position for a greater period of time. After his accession in Great Britain, George's relationship with his son (which had always been poor) worsened. George Augustus, Prince of Wales, encouraged opposition to his father's policies, including measures designed to increase religious freedom in Britain and expand Hanover's German territories at Sweden's expense. In 1717, the birth of a grandson led to a major quarrel between George and the Prince of Wales. The King, supposedly following custom, appointed the Lord Chamberlain (Thomas Pelham-Holles, 1st Duke of Newcastle) as one of the baptismal sponsors of the child. The King was angered when the Prince of Wales, disliking Newcastle, verbally insulted the Duke at the christening, which the Duke misunderstood as a challenge to a duel. The Prince was told to leave the royal residence, St. James's Palace. The Prince's new home, Leicester House, became a meeting place for the King's political opponents. The King and his son