Early-18th-century Whig plots
During the early 18th century, Great Britain was undergoing a government shift into a two party system. The leading conservative political grouping, the Tories, was the primary political party, but at the turn of the 18th century the Whigs, a liberal faction, had begun to rise in influence.
Source: Wikipedia — Early-18th-century Whig plots (CC BY-SA 4.0)