David Cameron has warned peace in Europe could be jeopardised if Britain were to leave the EU.
The prime minister emphasised the UK's historic links with continental Europe as he made a "patriotic case" for a Remain vote.
He ranked 2016 with other turning points in European history including the Spanish Armada in 1588, Blenheim in 1704, Waterloo in 1815, the First World War in 1914, the Battle of Britain in 1940 and the fall of the Berlin Wall in 1989.
"Britain has a fundamental national interest in maintaining common purpose in Europe to avoid future conflict between European countries," he added.
"And that requires British leadership, and for Britain to remain a member."
Brexit campaigner Boris Johnson is to deliver his own speech today before heading out on a campaign battle bus tour of the country.
A Vote Leave spokesman said: "Claims that leaving the EU and taking back control would somehow lead to war smack of desperation from a campaign failing to make the case for the EU and our continued payment of £350 million to Brussels every week.
"The PM's words are deeply ironic given the EU's own border agency says the EU's borderless policy is making the whole of Europe less safe. The safe option is to vote Leave."
The EU referendum will be held on June 23.