Are you on Win11?

I had this issue too, and yes. Compatibility mode?

Same Issue. Window 11.

If you are on Win11, do below:


1. Launch the Game – Start Total War: Rome II
2. Open Task Manager
Press Ctrl + Shift + Esc to open Task Manager.
Alternatively, you can right-click on the taskbar and select Task Manager.
3. Go to the Details Tab
In Task Manager, click on the Details tab at the top.
Look for rome2.exe in the list of running processes.
4. Set CPU Affinity
Right-click rome2.exe and select Set Affinity from the dropdown menu.
5. Unselect Some CPU Cores
A window will appear showing which CPU cores the game is using.
Uncheck a few cores (for example, if you have 6 cores, uncheck CPU 9 to 11).
Click OK to apply the changes.
6. Resume the Game

This fix can be applied even if game already froze.

MS messed up last Win11 update and it causes crashes in many games.