Hi there h4rp00n33r,
At the moment there is no setting within Anno 1800s menu to select which preferred monitor you would like to use.
There are several tricks you can perform though to make sure your game opens up on your desired monitor. Here are two you can try -
-Set your second monitor as your main monitor in the Display settings in Windows
-Launch the game
-When the game loads and appears on your 2nd monitor, close the game
-Set your first monitor as the primary monitor back in the Windows Display settings
-Launch the game again, it should be on your desired monitor
If the above workaround does not work, try this -
-In Uplay, select the options
-Find and select Windowed Mode and uncheck Borderless options
-Find the game launch it
-After the game starts, drag the window to the correct monitor
-Exit the game
-Launch Uplay again
-Go into the Uplay options and this time, ...
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