Here's another unusual unit represented for my Pre-Bardin-uniform project. It's a soldier of the Veterans of Rome.
I found this uniform in a book filled with old Knoetel uniform plates. Napoleon annexed the Papal States in 1810, following a number of disputes with the pope. At this time, the Papal State army was considered to be the most worthless of the continent. Whoever was found worthy of serving in a regular unit, was transferred to the regiments of the Kingdom of Italy.
However, there was still a bunch of men left - and as it was considered to have these people rather in a uniform and under some sort of control then having these men roaming the streets, the battalion 'Veterans of Rome' were raised as a military unit for local security purposes.
If used in wargaming scenarios, I would say that this unit is merely militia with a minus on morale and combat abilities.