Ocean liners as cruisers, troopships, and hospital ships

How did countries use ocean liners during the two world wars?

Most used them in similar ways: as armed merchant cruisers, troop transports, or hospital ships, depending on speed, capacity, and operational need.

Countries generally assigned ocean liners the same wartime roles as Britain. As armed merchant cruisers, they could operate far from home, carry boarding crews, and capture merchant ships while freeing warships for other work. Their speed and ability to carry thousands of people suited troop transport. Those same qualities also made them useful hospital ships.