Stanley Baldwin was the last Tory prime minister to call a December election in 1923, which he lost

If Boris Johnson believes that a December election will solve his problems, then perhaps he has not been paying attention to his history books.

The last time a general election was held in December was 1923. It was called by Stanley Baldwin, the Conservative prime minister who moved into No 10 after Andrew Bonar Law became too ill to continue and resigned in May after 209 days in office. He died from throat cancer in October.

Baldwin could have waited with a comfortable majority for another four years before going to the country. The national mood was gloomy, however, with high unemployment and continuing industrial unrest. He believed that he needed to win a renewed mandate from the people for his policy of protectionist tariffs