During “Secessions of the Plebians” the common people rebelled by simply abandoning the city and leave the aristocrats to themselves.
The upper classes were left servantless; shops and workshops shut down; commercial transactions came to a halt.
The main grievance seems to have been nexum (debt-bondage). As a debtor, you might be imprisoned and beaten by certain money-lenders; worse, you could be sold as a slave.
Interestingly, nexum was such a cultural institution by then, plebs may have simply been calling for the government to force creditors to be fair to their debtors.
The Senate solution? They appointed a dictator to quell the plebs and force them into military service to fight against the Aequi and Volsci peoples.
That war accomplished, the Senate immediately tried to do it again. They attempted to force the plebs into war without forgiving any debts, under the claim that they had already taken an oath to serve in the army.
A story recorded by Roman historian Livy has a former army officer stirring things up when he threw himself into the forum.
“Wasted, pale and emaciated”, he was still recognized by the people as a former army commander.
One plebeian, Lucius Sicinius Vellutus proposed that the people should leave the city en masse and go to Mons Sacer, the Sacred Mountain, three miles away.
The people followed his advice. When they arrived they set up camp and fortified it with ramparts and trenches and subsisted there for months.
Terrified by the potential consequences of the secession, especially the city’s vulnerability to attack, the patricians offered conditions for reconciliation.
This first-ever general strike was so effective that the commoners were given their own magistrates, the plebeian tribunes.
Through five Secessions of the Plebians between 494 BC and 287 BC, the plebs slowly established their own set of institutions.