Arrived in Mexico City, the Belgian Legion embarks on the expedition. She will participate in a number of small fights and especially cross from North to South the ephemeral empire of Maximilian and Charlotte in endless marches. During the clashes, the Belgians, officers as well as soldiers, will show bravery in the face of an enemy in permanent redundancy. Affected by illnesses as much as by bullets, just over half of the contingent returned to Belgium in 1867, to the indifference of their homeland.