Trade

You can use Trade under the force command [Sanction] to trade with foreign countries such as Daqin (Rome), Anxi (Parthia), Guishuang (Kushan), and Tianzhu (India). Through trade, you can obtain special benefits, such as specialty items and tactic tomes that cannot be found elsewhere.
Your force must be at the rank of Lt. Governor or higher to trade. You must also first obtain the Geographic Advantage of a specific province before trading with each foreign country. You can appoint up to 5 officers under your control to be trade envoys. When your envoy arrives at the target nation, your friendship will increase. However, your friendship with foreign nations that are at war with the target nation will decrease. Once friendship with the target nation reaches a certain level, you may receive a specialty item, a foreign technology, or a tactic tome.
If you have already dispatched an envoy to a foreign nation, you cannot dispatch another to that nation until the previous envoy returns.
Trade missions will continue even in the following cases.

The nations that can be traded with, and their required Geographic Advantages, are as follows.