Settlers United is a collaborative Community Project created by modders from both the Settlers III and Settlers IV communities to bring both communities closer together on a shared platform. The project was originally founded in summer of 2021 during the closing days of the Settlers IV World Championship. Since then, it has become one of the biggest fan projects in the entire Settlers community.
Settlers United provides a new client software to easily find and host Settlers III and Settlers IV matches. Only one click is needed to join an existing lobby.
Additionally, several bugs and glitches in both games have been fixed - this is the most stable experience both games have ever had.
Settlers United additionally contains the results of many smaller and larger successes in reverse engineering, which the lobby host can opt into. These include increasing the amount of settlers each player can have, activating the "coalfix" (called Transport+) as well as more substantial balance changes such as UBO.
The client can also automatically download custom maps for both games from a shared library - for multiplayer maps, this also ensures that all players are on the latest version and have the map installed correctly.