Charles's tactics for the insurgents in Rome proved highly effective.
Just as the Papal Guard had compressed more than three thousand demonstrators near the Borgo district and was preparing to arrest the leaders, several hundred insurgents armed with Austrian M1754 Flintlock Guns suddenly charged down from the hillside.
Yes, Rome had been known since ancient times as the "City of Seven Hills," for it contained seven low hills. Though the Borgo district lay outside the Seven Hills, the terrain around it was still rolling.
Arceo, a retired officer from Modena, shouted himself hoarse ordering the soldiers to hold formation, barely managing to keep the more than five hundred men from scattering. When they reached a point three stories above the flat ground, they stopped and began firing at the Court Guard.
Though the gunfire was ragged and the accuracy abysmal, the Court Guard had never expected an attack from their flank and instantly fell into chaos. The protest crowd that had been driven away turned under the Free Rome Party's organization and lunged at the Pope's soldiers.
In less than forty minutes, the Papal Guard left behind more than two hundred corpses, with another hundred and fifty men captured. The more than four hundred who escaped were also in full rout.
With victory in the first battle, the insurgent populace's morale was instantly fired to its peak. Those who had remained on the sidelines no longer hesitated and joined the uprising in droves.
Almost at the same time, among the marchers around Capitoline Hill in the city center, several hundred people suddenly drew guns hidden on their bodies. Shouting, "The Holy See's lackeys have been defeated!" they surrounded Rome City Hall.
Rome in this era had no office such as mayor. City Hall was filled with officials appointed by the