“We chose actors who weren’t known so they didn’t detract from the story,” says director Ringan.
The RBL will receive 50p from every £1 bar sold of Belgian chocolate made in the town of Ypres, scene of one of the war’s bloodiest battles.
Legion’ fundraising director Charles Byrne said: “This campaign is particularly important – 100 years on from the 1914 Christmas truce, it remembers the fallen while helping to raise vital funds to support the future of living.”
While most feedback for the 3min 20sec ad is positive, others on Twitter claim it is “profoundly distasteful” and “terribly exploitative”.
The Advertising Standards Authority said there had been more than 130 complaints since it was first shown during Wednesday night’s Coronation Street.
Most said it was offensive to use First World War imagery to promote a business or that it was not clear from the outset that it was an advert.
Neil Kelley, an advertising expert at Leeds Beckett University, said it made him feel “unclean”.
He added: “It’s a lovely story from history but I find it upsetting they’ve used the First World War as a vehicle to promote a supermarket.
“The sentiment behind it, supporting the RBL, is sound, but there’s something that doesn’t sit right with the use of the war. It doesn’t bring home any of the horrors... I think there’s a possibility veterans may be aggrieved too.”
An ASA spokeswoman said: “We will carefully assess the complaints to establish whether there are grounds for further action.”
Sainsbury’s said the advert was meant to “raise awareness and funds during this centenary year”.
A spokesman added: “We recognise the Christmas truce is an emotive and cherished story... which is why we have worked with the Legion and experts to ensure we tell it with authenticity and respect.”
The 1914 Christmas truce also inspiration two long-ago pop videos – Paul McCartney’s Pipes of Peace in 1983 and The Farm’s All Together Now in 1990.
Taff Gillingham, co-founder of Khaki Devil, the firm that operates the Suffolk trenches where filming took place, disagrees with the advert critics.
He said: “If we think somebody is making a programme that’s disrespectful we just won’t be part of it. We’ve turned down plenty of stuff in the past.
“The Christmas truce is something very close to my heart and there’s no way we would’ve done it if it was insulting to the old boys. And all the old boys I knew... I think they would have loved it.”