As a result, both clans supported Montrose's Royalist campaign of 1644–1645, in hopes of regaining them. When Charles II regained the throne in 1660, the Rescissory Act 1661 restored bishops to the Church of Scotland. This was supported by many chiefs since it suited the hierarchical clan structure and encouraged obedience to authority. Both Charles and his brother James VII used Highland levies, known as the "Highland Host", to control Campbell-dominated areas in the South-West and suppress the 1685 Argyll's Rising. By 1680, it is estimated there were fewer than 16,000 Catholics in Scotland, confined to parts of the aristocracy and Gaelic-speaking clans in the Highlands and Islands. When James was deposed in the November 1688 Glorious Revolution, choice of sides was largely opportunistic. The Presbyterian Macleans backed the Jacobites to regain territories in Mull lost to the Campbells in the 1670s; the Catholic Keppoch MacDonalds tried to sack the pro-Jacobite town of Inverness, and were bought off only after Dundee intervened. Highland involvement in the Jacobite risings was the result of their remoteness, and the feudal clan system which required tenants to provide military service. Historian Frank McLynn identifies seven primary drivers in Jacobitism, support for the Stuarts being the least important; a large percentage of Jacobite support in 1745 Rising came from Lowlanders who opposed the 1707 Union, and members of the Scottish Episcopal Church. In 1745, the majority of clan leaders advised Prince Charles to return to France, including MacDonald of Sleat and Norman MacLeod. By arriving without French military support, they felt Charles failed to keep his commitments, while it is also suggested Sleat and MacLeod were vulnerable to government sanctions due to their involvement in illegally selling tenants into indentured servitude. Enough were persuaded, but the choice was rarely simple; Donald Cameron of Lochiel committed himself only after he was provided "security for the full value of his estate should the rising prove abortive," while MacLeod and Sleat helped Charles escape after Culloden. Collapse of the clan system In 1493, James IV confiscated the Lordship of the Isles from the MacDonalds. This destabilised the region, while links between the Scottish MacDonalds and Irish MacDonnells meant unrest in one country often spilled into the other. James VI took various measures to deal with the resulting instability, including the 1587 'Slaughter under trust' law, later used in the 1692 Glencoe Massacre. To prevent endemic feuding, it required