La Grange was named for a county in Indiana. California Shipbuilding at Wilmington laid her down under a Maritime Commission contract on 26 June 1944 and launched her on 1 September. Mrs. Albert Krutcher sponsored the ship. The Navy acquired her on 10 November and commissioned her the next day. Captain Frank R. Walker was in command.
After shakedown and landing practice she left San Diego on 1 January 1945 and reached Manus on 18 January. She carried cargo and passengers onward to Hollandia and the Philippines, then joined Transport Squadron 17. About a month of preparation followed. She sailed from Dulag Harbor with the western islands attack group for Okinawa, the Pacific war's largest amphibious operation. On 26 March she was off Kerama Retto and landed the advance party that seized that small group of islands. The islets thereafter served as a forward anchorage for fuel, upkeep, and supply while Okinawa was being taken. Through the next month she remained offshore and kept the troops on shore supplied. Saipan saw her again on 6 May. A fortnight later naval passengers boarded for a passage whose destination was San Francisco.
Operational duty picked up once more when she arrived at Eniwetok on 11 July. She headed back toward Okinawa on 29 July and, a week after that, anchored in Buckner Bay to unload cargo wanted in the closing days of the fighting. On 13 August, still at anchor, she came under air attack. Antiaircraft fire was on target, yet one kamikaze got through with a fifty-pound bomb and struck the superstructure. A second plane clipped the head of a kingpost and dropped into the sea about twenty yards off the side. The transport was heavily damaged. Twenty-one of her men were killed and eighty-nine wounded.
Hostilities ceased on 15 August. She mended what she could and made ready for the trip home. Veterans boarded at Guam, she sailed on 6 September, and San Francisco took her in on 21 September. La Grange was decommissioned there on 27 October 1945 and given back to the War Shipping Administration. One battle star was awarded for her service in the war.