A Knight Might Live Little Better Than His Peasants

At the bottom of the scale is the small fief of a single knight. As a rough estimate, it takes the labor of fifteen to thirty peasant families, working a holding of forty to one hundred hectares, to support one knight, his family, and his warhorse. (A hectare is 10,000 square kilometers, or about 2½ acres.) On such a small manor, the knight lives little better than his peasants.

— Who Lives In That Castle?, Dragon Magazine #80