Each parish will begin generating flags every 24-48 hours once it has an elected leader. Flags are needed to construct buildings in the parish capital. The members of a parish can use their village armies to attack other parish castles to steal their flags, or the parish steward can use the parish army to steal flags. Factions will often work together to take flags from enemies or inactive parishes to help their own capitals grow more quickly.
Once a parish has 100 flags, no additional flags can be stolen from other parishes! The parish steward will need to use some of the flags before more flags can be acquired.