[3] Cammell Laird & Company in Birkenhead built Samaria for Cunard Line, launching her on 27 November 1920.

Intended to augment Cunard's transatlantic service Samaria ran on the Liverpool to Boston and New York City route with periodic stops in Cobh, and appealed to those first and second class passengers looking for comfort at reasonable rates and who were not in a hurry.

However the end of unrestricted immigration to the United States in the mid-1920s necessitated the first of several reconfiguration of passenger accommodations as third class became "tourist.

In 1941 the ship was taken over by the Royal Navy and served as a troopship until 1948 when she was returned to Cunard and refitted for passenger service.

Between 1948 and 1955 Samaria was assigned almost exclusively to the Canadian route with service to Montreal, Quebec, and Halifax along with her sister-ship RMS Scythia.