Whigs
The Whigs were one of the two main political parties in Britain between the 17th and the 19th centuries, transmuted into the Liberals in the 19th century.
The term itself derives from the Scottish word "whiggamore", which means something like thief or plunderer. This denomination was given to the members of the party in the 17th century by the Tories during the Exclusion Crisis to brand the opponents of James, Duke of York. The first Whigs were dominated and coordinated by Anthony Ashley Cooper, first Earl of Shaftesbury. He wielded his influence in Parliament (for the passing of the Exclusion Bills), but he also tried to shape public opinion by means of (almost modern) canvassing, posters, pamphlets. The "Green Ribbon Club" became the centre of Whig activities.
The Whigs put great emphasis on parliamentary authority. They claimed that political authority derived from the people (or from people who owned property), and they acted from the assumption that an elite (or an oligarchy) should rule the country. Thus, if the monarch did not care about their interests, they might resist him. So, they played an important role in the Glorious Revolution.
In the 18th century, Whigs dominated both Parliament and government. Eminent Whig politicians were Robert Walpole and Henry Pelham.
Sources:
Oxford Companion to British History
The Companion to British History