Ertugrul Cavalry Regiment Fausto Zonaro

The picture has something of this: people, military, group, army, soldier, many, weapon, man, uniform, war, group together, gun, cavalry, wear, rifle, skirmish, crowd, flag, military uniform.
Perhaps it’s a painting of a group of men riding on the backs of white horses with red flags on either side of them and a blue sky in the background.