From: Raymond E. Feist
Date: 28 November 1998
Quite a long time, actually. 1) you have an agrarian economy, hence you have lots of people growing lots of food pretty much everywhere 2) you have magic, which means that under the right circumstances, the King can call upon magical help for moving food and arms one way, wounded another, and getting damaged soldiers healed.
Best, R.E.F.
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