An unprecedented search for up to a million Britons whose ancestors fought at Waterloo is being launched ahead of the 200th anniversary of the battle.

Hundreds of thousands of people living in the UK are estimated to have forbears who took part in the fighting in 1815.

Experts believe many are "totally unaware" of their relatives' involvement in the battle and are calling on people to research their family histories to see if there is a link.

The campaign is part of a number of events planned to commemorate the battle, which saw the final defeat of Napoleon Bonaparte and marked one of the most crucial events in European history, in the months before the 200th anniversary in June.

Those with verified family connections will be given the chance to appear at one of the highest-profile events later this year.

James Morrow, honorary secretary of Waterloo 200, which is overseeing commemorations, said there are thought to be a total of between one and two million people around the world who are descended from those involved in the battle.

A large proportion of those are believed to be living in Britain.

Around 350 people have already come forward to register the details of their ancestors, with a number submitting accounts of their forbears' involvement in the battle on June 18 1815.

Organisers hope the campaign will help as a tool to revive flagging interest in and understanding of the significance of the battle.

Sir Evelyn Webb-Carter, chairman of Waterloo 200, described the event as a "defining moment in European history".

"It was, I think, one of the most decisive battles of all time," he said.

"A very distinctive, important battle that had defining consequences for years to come - a truly significant landmark event in history. It was the battle that made Europe.

"Yet today many people think of Waterloo as merely a train station or an Abba song."

Those wanting to investigate whether they have a family connection can see the names of the 39,009 British army officers and men who took part at www.findmypast.co.uk

Details of the Waterloo 200 campaign can be found at www.waterloo200.org/