[9] When launched in 1927 she was also the largest merchant ship yet built in the US,[10] although she was a modest size compared with the biggest European liners of her era.

[11] The ship's keel was laid 20 March 1926 as hull number 325, launched on 1 October 1927 and delivered to American Line on 13 January 1928.

California was a steamship, with oil-fired furnaces heating her boilers to power two steam turbo generators that ran at a constant 2,800 RPM.

[10] In June 1937 the United States Congress withdrew all maritime mail subsidies, which by then included a total of $450,000 per year for Panama Pacific's three liners.

[10] On 10 June 1938 the United States Maritime Commission (MC) purchased the ship, made repairs and placed it under an operating agreement with Moore McCormack Line 13 January 1939.

[5] All three sisters were fireproofed to comply with Federal safety regulations,[17] which had been revised as a result of the fire in 1934 that destroyed the liner Morro Castle.

California's state rooms were improved, her air conditioning was extended to her tourist class accommodation, a new swimming pool was installed, and her after deck was rebuilt with the addition of a veranda café.

[2] On 4 October 1938[5] Moore-McCormack Lines, Inc., contracted to operate California, Virginia, Pennsylvania and 10 cargo ships between the US and South America[17] as part of President Franklin D. Roosevelt's Good Neighbor policy.

[5] Moore-McCormack renamed the three passenger liners Argentina, Brazil and Uruguay, and assigned them to the fleet of its American Republics Lines subsidiary.

[5] The ship, a large and fast vessel capable of independent voyages without escort, was operated by WSA agents and allocated in support of Army troop transport requirements with a passenger capacity of 4,473.

[8] She left Wellington Harbour on 28 April carrying Royal New Zealand Air Force cadets, and arrived in San Francisco, California on 14 May.

[5] On 12 February 1943 in the North Atlantic the oil tanker USS Salamonie suffered a steering fault and accidentally rammed Uruguay amidships.

[5] One injured soldier, Sergeant Cecil Davis,[8] landed on the tanker's deck, where he was not discovered until Salamonie had changed course to Bermuda for repairs.

[8] President Franklin D. Roosevelt decorated Uruguay's Master, Captain Albert Spaulding, with the Merchant Marine Distinguished Service Medal for saving many lives, his ship and her cargo.

[8] On 15 February 1946 she left Yokohama carrying European diplomats and dignitaries whom Japan had detained during the Second World War, and wounded US soldiers.

[5] On 25 June 1946 Uruguay reverted to the Maritime Commission and Federal Shipbuilding and Drydock Company of Kearny, New Jersey was awarded a $4,437,000 contract to convert her back into an ocean liner.

[21] On 23 January 1948 Uruguay left Todd Shipyards for an 18-hour sea trial, and the next day the Maritime Commission restored her to Moore-McCormack Lines.

[5] Captain Spaulding resumed command and on 30 January Uruguay started a nine-day Caribbean cruise to Nassau and Havana.

[5] On 10 February 1948 Uruguay was given the US Navy Reserve pennant and her library was dedicated in memory of Thomas K Locke, a Moore-McCormack employee who died on active service as an infantry captain in the Second World War.

[5] On her first voyage under Lane's command, Uruguay achieved her fastest time from Rio de Janeiro to Trinidad, covering the distance in six days, 14 hours and 42 minutes and averaging 19.95 knots (36.95 km/h).

[5] She was transferred to the US Federal Government and was laid up as part of the James River, Reserve Fleet at Fort Eustis, Virginia.

[5] In 1940 Leopold Stokowski and his All-American Youth Orchestra toured South America, and recorded native Brazilian music aboard Uruguay.

[5] In February 1943 the American Football coach Bear Bryant was en route to North Africa aboard Uruguay on the voyage when USS Salamonie accidentally rammed her.

[23] In November and December 1944 Bernie Abrams, Doc Blanchard, Glenn Davis, Alexander Haig and Brent Scowcroft were among the West Point Cadets who sailed from New York to Baltimore and back aboard Uruguay.