When President Hollande attends the centenary on Friday, he will be the first French head of state at a Somme commemoration in more than 80 years, reports the BBC.
President De Gaulle did not attend the 50th anniversary in 1966. Nor have his successors been at any subsequent event.
In fact the last time a French head of state went to a Somme commemoration was in 1932 when the long-forgotten Albert Lebrun helped inaugurate the Thiepval memorial alongside the future King Edward VIII.
In a way this is very odd, because the 1916 Battle of the Somme was not just a British battle - it was a French battle too.
The broad outlines of the Somme offensive had been drawn up by the Allies the previous winter - and initially the plan was for a joint attack on the German front with the British and French contributing roughly equally.
But then came the German attack on Verdun in February, which forced the French to divert resources to the east. In the end their share in the Somme was about one-third, to the British two-thirds.