Oil on canvas, 21.5cm by 35.5cm.
Courtois trained with his artist father in France before travelling to Italy, where he served as a soldier.
On leaving the army, he returned to painting, working mainly in Rome and Florence, where he specialised in military scenes and came to be regarded as the finest painter of his day in the genre.
He also painted in several churches and monasteries of the Society of Jesus, after becoming a Jesuit in Florence in 1655.
