Heres how it works:

- Every now and then, you will get a notification that a Treasure fleet from (England, France, Spain or Holland) is arriving in the Carrabean. These are the ships that come from Europe to buy one of the 4 "Colonial" Goods and in exchange, drop Settlers in the Port they bought it.

- Treasure fleets only visit Governor or Viceroy port from his respective nation. Unless you have the "Harbour Master" DLC, then if you own the town, you can build the "Embassy" that allow treasure fleet to visit your port too, click on the building and set wich nation the embassy represent.

- You can see what convoy is a treasure fleet by placing your cursor above a convoy in the naval chart and look for a "Chest" icon.

- When a treasure fleet visit a port, it will buy directly from the Port Market (NOT from your warehouses) and buy all the colonial good stored in the market until the price bar have 1 green slot or until the convoy cargo is full. It will drop an amount of settler equal to the number of barrel bougth in the port, unless too much settler are already in a port. In any case it will buy the good, even if they dont leave settlers because the port is full.

- If the convoy cargo isnt full after visiting a port, it will go to the next eligible port (Viceroy, Governor or Player owned ports with embassy built for the respective nation)

- Viceroy Port has crown over the port name and governors port have a ring, if you click on your port's embassy, you can see how much good and settler have been traded to this town recently from the treasure fleet.

- The 4 "Colonial" Goods are: Dye, Coffee, Cacao, Tabbacco, sell them in the eligible port where you want new settlers. You can even sell a large amount at a poor price, just to fill the port with it when you want a large amount of settlers. You should try to time this supplying with the Treasure fleet arrival (see message, in the world section)