Anno 1800 ; multiplayer requires an active internet connection to authenticate through Ubisoft Connect . Multiplayer Connection Summary
does not feature a dedicated, "offline" LAN mode, you can play with others on the same local network by using the standard online multiplayer system. This requires all players to have an active internet connection to authenticate with Ubisoft Connect anno 1800 lan multiplayer link
Even on a perfect local network, issues arise. Here is the most common error: "Unable to join session. The connection to the host has been lost." Anno 1800 ; multiplayer requires an active internet