Summarize the various ways royal families were affected by the Great War.

The very last combat veteran of the First World War, Claude "Chuckles" Choules of the Royal Navy, died in an Australian nursing home last year, aged 110. The last non-combat veteran, Florence Green, an RAF steward, died this February in King’s Lynn, also aged 110.

So the First World War has almost entirely deserted living memory. And yet its memory stays strong - and grows ever stronger - among those born decades after it ended. More than 300,000 people still visit the battlefields in northern France every year. First World War dramas come thick and fast: Parade’s End, Downton Abbey, that revered, much-repeated last scene in Blackadder.

Literature, too, goes back and back to the trenches. Pat Barker has just published Toby’s Room, a First World War novel, 21 years after Regeneration, the first book in her war trilogy. Yesterday, David Cameron talked of how Michael Morpurgo’s War Horse and the novels of Sebastian Faulks have kept the First World War vivid for new generations.

The Prime Minister was making a speech at the Imperial War Museum in London, pledging £50 million towards commemorations of the centenary of the beginning of the First World War in less than two years’ time. There will be ceremonies, too, to recall Jutland, Gallipoli, the Somme, Passchendaele and the Armistice; as well as special events at the Imperial War Museum, educational initiatives and Lottery-funded commemorations at war memorials across the country.

Why has the First World War stuck so doggedly in the modern mind? The Second World War is rightly prominent, too - but it still has thousands of surviving veterans to reinforce its impact every year at the Cenotaph. The Boer wars, which ended in 1902, have been largely forgotten - even in an era of frantic anniversary celebrations.