Take somebody else's town, loot it and leave it. Then use that money to build more temples and such.

Other than that, if things are as desperate as you describe, invade someplace with human waves of peasants. Leave each group under a captain and autoresolve.

If things are as bad as you describe, even a disasterous campaign that kills off mounds of unwanted peasants would be better.

Just make a bunch of peasants and keep marching them into somebody's territory, preferably a weak barbarian state on its last legs.

If at all possible, take the province. Then you'll have someplace to take the peasants to and just disband them.

I would suggest other things, like temples and so forth, but suggestions like that are no good without money.

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I wonder what happens if you have an ship full of peasants and then disband the ship? Does a ship have to be in port to disband?