British political parties date from the 17th century, when the Whig and the Tory parties appeared during the time of the Revolution of 1688. Whigs believed in a strong Parliament and came from the landed classes who were allied with the merchants and nonconformist or non-Anglican Protestants. Tory supporters came from the landed aristocracy and were defenders of the king and the Church of England. In the 1800s the Whigs merged with other parties interested in social reform to form the Liberal Party. The Tories took on the additional name of the Conservative Party in the 1830s in order to appeal to a broader electorate, and both names are used interchangeably. The Conservative Party is still a major party in the United Kingdom, but the Labour Party, founded around the turn of the 20th century, grew to become the primary opposition to the Conservatives, taking the place of the Liberals. The Liberal Party evolved into the Liberal Democrat Party, the third most popular party in Britain.
Since its founding days, the Labour Party has drawn traditional financial and electoral support from the trade unions. The Labour Party has a socialist element, supporting state control of important industries and a more equal distribution of wealth. After World War II (1939-1945), the Labour government nationalized a number of industries and established the welfare state, which provided people with social security, unemployment insurance, and the National Health Service. Subsequent Conservative governments denationalized industries but kept the National Health Service and the main provisions of the welfare state. In recent years, trade union membership has declined, as has union influence in the Labour Party. At the same time, the Labour Party has moved toward the political center; in 1995 it gave up its commitment to socialism and the nationalization of industries.
The Conservative Party favors private enterprise and minimal state regulation, and accepts the mixed economy, which involves private ownership of businesses with some government control. Although a mixed economy entails more public spending than conservatives in the United States would support, the British business community is a strong supporter of the Conservative Party because it has historically supported private enterprise and a free market. In the 1980s the Conservative government under Prime Minister Margaret Thatcher sought to increase private enterprise and reduce public legislation by introducing more competition into the National Health Service and by selling off public housing. Thatcher's domestic policies were highly controversial and eventually led to the downfall of the Conservative government in the mid-1990s.
The most important of Britain's minor parties is the Liberal Democrat Party, formed in 1988 from the remnants of the Liberal Party and a majority of the Social Democratic Party. Other parties include the Scottish Nationalist Party; Plaid Cymru, the Welsh nationalist party that seeks self-government for Wales; and parties in Northern Ireland-Sinn Fein, the Ulster Unionist Party, the Democratic Unionist Party, and the Social Democratic and Labour Party. The two members of Sinn Fein elected to Parliament in 1997 refused to take an oath of allegiance to the queen, and because of this were barred from taking their seats.
The Labour Party won the May 1997 general election by a landslide, taking 43.2 percent of the vote and 418 of the 659 seats in Parliament. The Conservative Party received 30.7 percent of the vote and 165 seats. The Liberal Democrats doubled their number of seats in Parliament to 46 after gaining 16.8 percent of the vote.
The current voting system is called "first past the post." This means that the party and candidates receiving the most votes win the election and become the party in power even if they do not receive more than 50 percent of the vote. Under this system, smaller parties have proportionally less representation in Parliament than their share of the popular vote, as their candidates often do not garner enough votes in constituencies to send members to Parliament. As a result, some people support a system of proportional representation, which is used in a number of European countries. In such a system, which can take various forms, the number of seats a party receives in the legislature is proportional to the number of votes the party receives in the election. Critics of proportional representation assert that it produces too many political parties and leads to weak governments. A commission was set up in 1997 to review voting reform and consider switching to proportional representation.