The Eldorado was launched on October 26, 1943 as Monsoon by the North Carolina Shipbuilding Company in Wilmington, North Carolina, under a Maritime Commission contract, sponsored by Mrs. P. A. Peeples; transferred to the US Navy on February 1, 1944; converted by Bethlehem Steel Corporation in Brooklyn, New York; and commissioned on  August 25, 1944, with Captain Jesse Wallace in command.

1944
The Eldorado sailed from Naval Station Norfolk on September 15, 1944 and arrived at San Diego on September 29 to embark Rear Admiral Lawrence F. Reifsnider who broke his flag as Commander, Amphibious Group 4.
 In November, it sailed to Pearl Harbor and there became the flagship for Vice Admiral Richmond K. Turner, Commander, Amphibious Forces, Pacific.

1945
On January 27, 1945, after rehearsal landings in Hawaii, the command ship sailed for the Marianas and further preparations for the landing on Iwo Jima.
The ship also carried General Holland Smith, USMC, and his staff, and Secretary of the Navy James Forrestal and his party when it sailed from Saipan on February 16 for Iwo Jima.
The Eldorado lay off Iwo Jima from February 19 to March 9, its passengers directing operations ashore and afloat.
It served as headquarters for war correspondents, and broadcast directly from the beachhead to the people at home through its facilities.
One of these correspondents was Joe Rosenthal of the Associated Press, who took the famous American flag-raising photo on Mount Suribachi.

The Eldorado arrived at Guam on March 12, 1945, and embarked Lieutenant General Simon B. Buckner, Commanding General of the 10th Army, then after rehearsals at Leyte in the Philippines, sailed off to the Hagushi Beaches, Okinawa, for the initial invasion landings on April 1.
The ship carried out the same type of duties it had performed at Iwo Jima.
Since both the Commander, Air Support Control Unit, and the Force Fighter Director Officer were embarked, Eldorado's combat information center was the central unit in the air defense against the day and night air raids.
General Buckner and his staff debarked on  April 18 to establish headquarters on the island itself, and until the ship's departure on May 18, it was visited by several guests, including Admirals Chester W. Nimitz, William F. Halsey, Jr. and Raymond A. Spruance and war correspondent Ernie Pyle.
The Eldorado was launched on October 26, 1943 as Monsoon by the North Carolina Shipbuilding Company in Wilmington, North Carolina, under a Maritime Commission contract, sponsored by Mrs. P. A. Peeples; transferred to the US Navy on February 1, 1944; converted by Bethlehem Steel Corporation in Brooklyn, New York; and commissioned on  August 25, 1944, with Captain Jesse Wallace in command.
1944
The Eldorado sailed from Naval Station Norfolk on September 15, 1944 and arrived at San Diego on September 29 to embark Rear Admiral Lawrence F. Reifsnider who broke his flag as Commander, Amphibious Group 4.  In November, it sailed to Pearl Harbor and there became the flagship for Vice Admiral Richmond K. Turner, Commander, Amphibious Forces, Pacific.
1945
On January 27, 1945, after rehearsal landings in Hawaii, the command ship sailed for the Marianas and further preparations for the landing on Iwo Jima. The ship also carried General Holland Smith, USMC, and his staff, and Secretary of the Navy James Forrestal and his party when it sailed from Saipan on February 16 for Iwo Jima. The Eldorado lay off Iwo Jima from February 19 to March 9, its passengers directing operations ashore and afloat. It served as headquarters for war correspondents, and broadcast directly from the beachhead to the people at home through its facilities. One of these correspondents was Joe Rosenthal of the Associated Press, who took the famous American flag-raising photo on Mount Suribachi.
The Eldorado arrived at Guam on March 12, 1945, and embarked Lieutenant General Simon B. Buckner, Commanding General of the 10th Army, then after rehearsals at Leyte in the Philippines, sailed off to the Hagushi Beaches, Okinawa, for the initial invasion landings on April 1. The ship carried out the same type of duties it had performed at Iwo Jima. Since both the Commander, Air Support Control Unit, and the Force Fighter Director Officer were embarked, Eldorado's combat information center was the central unit in the air defense against the day and night air raids. General Buckner and his staff debarked on  April 18 to establish headquarters on the island itself, and until the ship's departure on May 18, it was visited by several guests, including Admirals Chester W. Nimitz, William F. Halsey, Jr. and Raymond A. Spruance and war correspondent Ernie Pyle.
USS Eldorado (AGC-11)