General Election 2015: Tory decline in Scotland

Their numbers fell precipitously in the 1980s

Since 2005, David Mundell has been Scotland’s only Tory MP (Getty Images)

The Conservatives once dominated Scottish politics. Support for the party rose rapidly during the 1920s, and peaked in the general election of 1931, when the Tories gathered more than a million Scottish votes.

In that inter-war period, it was traditional in cities such as Glasgow that Protestants voted Tory, while Catholics voted Labour. After the war, the working class Protestant vote largely switched to Labour, but even in 1979, the year Margaret Thatcher came to power, there were 22 Scottish Tory MPs.

Their numbers fell precipitously in the 1980s – and in 1997 they were wiped out altogether. Their recovery began with the creation of the Scottish Parliament in 1999 and the adoption of proportional representation, which gave the Tories 18 MSPs. In 2005, David Mundell won Dumfriesshire, Clydesdale and Tweeddale, and for the next 10 years he was Scotland’s only Tory MP.