Military commander giving audience to two ambassadors in his camp [outside Bologna?]

A pen and brown ink and wash drawing showing a military commander sitting just outside his tent, flanked by two ambassadors standing on his right and two soldiers on his left. Behind the commander's tent, in the middle distance, a military camp can be seen with some more tents and a large platoon of soldiers marching on the right, and mounted soldiers on the left. In the distance on the left is a walled city [Bologna?] against a backdrop of two hills with watch towers.