Hoping to hold together a party with a small majority in parliament and facing resignations, the British prime minister takes the unusual step of letting members of his cabinet oppose the government ahead of a referendum on Europe.

The year was 1975 and that leader was Labour's Harold Wilson. But with current Conservative Prime Minister David Cameron's plans to hold a referendum on Britain's European Union membership increasingly echoing the last time Britons voted on staying in the bloc, it could just as easily be 2016.

Facing the prospect of members of his team quitting, Cameron used the same tactic as Wilson this month and bowed to pressure to allow ministers to campaign to leave the EU after he renegotiates Britain's relationship with the bloc.