This is how wars were won during the Romans's Empire (And other military). They were blockading a city. Nothing comes in, and nothing comes out. You starve the citizens out. Of course, if they did not give up, whoever had the blockade would start fining arrows and other things that could flame and burn the city down. In the Siege of Leningrad, Hitler and his nazi army blockaded Leningrad through the winter. Many thousands died of starvation. The United States came through the Gulf of Finland and was able to bring food supplies and weapons finally.

This is how wars were won during the Romans's Empire (And other military). They were blockading a city. Nothing comes in, and nothing comes out. You starve the citizens out. Of course, if they did not give up, whoever had the blockade would start fining arrows and other things that could flame and burn the city down.