Ulithi - History

History

The first European to find Ulithi was the Portuguese navigator Diego da Rocha, in 1526, but it remained undisturbed by Europeans until rediscovered by Captain Don Bernard de Egui in 1712, and later visited by Spanish Jesuit missionaries led by Juan Antonio Cantova in 1731.

Germany purchased the islands from Spain in 1898. They were occupied in 1914 by Japan at the outset of the First World War. Japan received them in 1920 as a League of Nations mandate.

As the Second World War moved west across the Pacific, the US Navy required a more forward base for operations. The Japanese had established a radio and weather station on Ulithi and had used the lagoon as an anchorage occasionally early in the war, but had abandoned it by 1944.

Ulithi was perfectly positioned to act as a staging area for the US Navy's western Pacific operations. The atoll is in the westernmost of the Caroline Islands, 360 miles (580 km) southwest of Guam, 850 miles (1,370 km) east of the Philippines and 1,300 miles (2,100 km) south of Tokyo. It is a typical volcanic atoll, with a coral reef, white sand beaches and palm trees. Ulithi's forty small islands barely rise above the sea, with the largest being only half a square mile in area. However the reef runs roughly twenty miles north and south by ten miles across, enclosing a vast anchorage with an average depth of 80 to 100 feet (30 m). The anchorage was well situated, but there were no port facilities to repair ships or re-supply the fleet.

On September 23, 1944, an army regiment of the 81st Division landed unopposed, followed a few days later by a battalion of Seabees. The survey ship USS Sumner surveyed the lagoon and reported it capable of holding 700 vessels. It became the undisclosed Pacific base for the major operations late in the war, including Leyte Gulf and the Okinawa operation. The huge anchorage capacity was greater than either Majuro or Pearl Harbor, and over seven hundred ships anchored there at a time.

The US Navy transferred the local islanders to the island of Fedarai for the duration of the hostilities. Next came what Admiral Nimitz called his "secret weapon", Service Squadron 10. Commanding officer Commodore Worrall R. Carter devised the miraculous mobile service force that made it possible for the Navy to create repair facilities and re-supply facilities thousands of miles away from an actual Naval port. Service Squadron 10 was called upon to convert the lagoon into a servicable naval station. Pontoon piers of a new design were built at Ulithi, each consisting of the 4-by-12-pontoon sections, filled with sand and gravel, and then sunk. The pontoons were anchored in place by guy ropes to deadmen on shore, and by iron rods driven into the coral. Connecting tie pieces ran across the tops of the pontoons to hold them together into a pier. Despite extremely heavy weather on several occasions these pontoon piers stood up remarkably well. They gave extensive service, with little requirement for repairs. Piers of this type were also installed by the 51st Battalion to be used as aviation-gasoline mooring piers near the main airfield on Falalop.

Within a month of the occupation of Ulithi, a whole floating base was in operation. Six thousand ship fitters, artificers, welders, carpenters, and electricians arrived aboard repair ships, destroyer tenders, and floating dry docks. The USS Ajax had an air-conditioned optical shop and a metal fabrication shop with a supply of base metals from which she could make any alloy to form any part needed. The USS Abatan, which looked like a big tanker, really distilled fresh water and baked bread and pies. The ice cream barge made 500 gallons a shift. The dry docks towed to Ulithi were large enough to lift dry a 45,000 ton battleship. Fleet oilers sortied to and from Ulithi to meet the task forces at sea, refueling the warships a short distance from their combat operational areas. The result was something never seen before: a vast floating service station enabling the entire Pacific fleet to operate indefinitely at unprecedented distances from its mainland bases. Ulithi was as far away from the US Naval base at San Francisco as San Francisco was from London, England. The Japanese had considered that the vastness of the Pacific Ocean would make it very difficult for the US to sustain operations in the western Pacific. With the Ulithi naval base to refit, repair and resupply, many ships were able to deploy and operate in the western Pacific for a year or more without returning to the Naval base at Pearl Harbor.

The Japanese had built an airstrip on Falalop. It was expanded and resurfaced, the runway running the full width of the island. The east end of the strip was extended approximately twenty feet past the natural shoreline. A number of small strips for light aircraft were built on several of the smaller islands. The Seabees completed a fleet recreation center at Mogmog island that could accommodate 8,000 men and 1,000 officers daily. A 1,200-seat theatre, including a 25-by-40-foot stage with a Quonset hut roof was completed in 20 days. At the same time, a 500-seat chapel was built. A number of the larger islands were used as recreational facilities and used as bases to support naval vessels and facilities within the lagoon.

The Japanese still held Yap. Early after the US occupation they mounted a number of attacks but caused no damage to the Seabees working on the islands.

On 20 November 1944 the Ulithi harbor was attacked by Japanese kaiten human torpedoes launched from two nearby submarines. The destroyer USS Case rammed one in the early morning hours. At 5:47 the fleet oiler USS Mississinewa, at anchor in the harbor, was struck and sunk. Destroyers began dropping depth charges throughout the anchorage. After the war Japanese naval officers said that two tender submarines each carrying four manned torpedoes had been sent to attack the fleet at Ulithi. Three of the suicide torpedoes were unable to launch due to mechanical problems and another ran aground on the reef. Two did make it into the lagoon, one of which sank the USS Mississinewa. A second kaiten attack in January 1945 was foiled when the I-48 was sunk by the destroyer escort USS Conklin. None of the 122 men aboard survived.

On March 11, 1945 two long range aircraft whose flight originated in Japan made a nighttime kamikaze attack on the naval base in a mission called Operation Tan No. 2. One struck the Essex-class aircraft carrier USS Randolph, causing moderate damage and killing a number of crewmen. The other mistook the baseball field on Mogmog for an aircraft carrier.

By March 13 there were 647 ships at anchor at Ulithi, and with the arrival of amphibious forces staging for the invasion of Okinawa the number of ships at anchor peaked at 722.

After Leyte Gulf was secured, the Pacific Fleet moved its forward staging area to Leyte, and Ulithi was all but abandoned. In the end, few US civilians ever heard of Ulithi. By the time Naval security cleared release of the name, there were no longer reasons to print stories about it. The war had moved on, but for seven months in late 1944 and early 1945, the large lagoon of the Ulithi atoll was the largest and most active anchorage in the world.