Trade

Trade is the business of buying and selling commodities. In the case of Battlemaster, the only tradable commodity is food, although wood will likely be the next commodity.

Region Lords

A region lord travels to either his region or a marketplace and creates an offer. Region lords of net food producers (rural regions) will typically create a sell offer, while region lords of net food consumers (cities) will create buy offers. Several region types are often close to a break-even, and may not create offers of either type, or may do so only rarely.

It is possible to restrict the sale of food to your realm only, or only allied realms. Realms at war are not allowed to trade at all.

It is also possible to use only one type of offer in a realm--either the city lords create buy offers, and region lords fulfill them, or the rural lords create sell offers, and the city lords agree to them.

Region lords can only trade within a limited distance of themselves. This means, however, that they can travel across the island and conduct a trade that sells or buys food from their region.

Stewards operate in the same way as region lords.

Traders

Traders must be at a marketplace to do business, unless they are a region lord, in which they can also do business in their own region. Traders have a much larger trading range than non-traders, over 500 miles in many cases.

Traders are the only class capable of brokering trades. To broker a trade, they must match up one or more buy offers with one or more sell offers in such a way that the quantity of food matches. In order to complete the trade, the trader must make a profit.

Production and Consumption

Each realm and region produces a certain amount of food every day. This is basically synonymous with supply. Likewise, all regions and realms consume an amount of food (unless they have zero population!) each day, and this is the same as demand.

Put another way, a region that produces more food than it consumes can be characterized as a supply region (and can export what it doesn't consume), whereas one that consumes more food than it produces is a demand region (and will need to import what it doesn't produce).