Recently, an old grave were discovered in Italy. On the grave was written a mysterious inscription (originally in italian but translated in english there).
Here lies an italian soldier who died in battle
12016485 is the multiplication of his day and month of death,
his age when he died, his number of children and finally,
the number of years between his death and Boru's death
Hint:
France was part of the war.
Hint2:
He had less than 10 children
Source: strongly inspired by Diophante.fr website