Vernet, Horace – Patrice de Mac-Mahon (1808-1893), duc de Magenta, président de la République Château de Versailles

The picture has something of this: people, wear, man, military, outfit, weapon, soldier, group, war, two, military uniform, skirmish, portrait, sword, uniform, veil, three, army.
Perhaps it’s a painting of a man in a military uniform standing in front of a group of men on a field with a flag and other men in the background.