Battle of Tinian
The Battle of Tinian was part of the Pacific campaign of World War II. It was fought between the United States and Japan on the island of Tinian in the Mariana Islands from 24 July until 1 August 1944. The battle saw napalm used for the first time.
At the Cairo Conference in December 1943, the US and British Combined Chiefs of Staff endorsed a two-pronged attack through the Central Pacific and Southwest Pacific Areas. On 12 March 1944, the Commander in Chief, Pacific Ocean Areas, Admiral Chester W. Nimitz, was directed to neutralize Truk and occupy the Mariana Islands. The Mariana Islands were targeted because of their location astride the Japanese line of communications. Tinian lay too close to Saipan to allow it to be bypassed and remain in Japanese hands. Following the conclusion of the Battle of Saipan on 9 July, Major General Harry Schmidt's V Amphibious Corps began preparations to invade nearby Tinian. The Japanese defending the island were commanded by Colonel Kiyochi Ogata, the commander of the 50th Infantry Regiment. This regiment was part of the 5,000 Army troops on the island. There were also about 4,000 Imperial Japanese Navy personnel on Tinian, the main force being the 56th Naval Guard Force, under the command of Captain Goichi Oie. Most of the island was surrounded by coral cliffs, so Ogata concentrated his forces on the southwest of the island, where the best landing beaches were located.
Major General Clifton B. Cates's 4th Marine Division landed on Tinian on 24 July 1944, supported by naval bombardment and the guns of the XXIV Corps Artillery, firing across the strait from Saipan. Instead of landing in the southwest, they landed on the northwest coast, where there were two small beaches that were lightly defended. These beaches were flanked by low coral cliffs that the marines were able to surmount with the aid of ramps mounted on modified amphibious tractors. A successful feint in the southwest by Major General Thomas E. Watson's 2nd Marine Division distracted defenders from the actual landing site on the north of the island. The 2nd Marine Division then landed behind the 4th Marine Division. The weather worsened on 28 July, damaging the pontoon causeways and interrupting the unloading of supplies, but on 30 July the 4th Marine Division occupied Tinian Town and the airfield. Japanese remnants conducted a last stand in the caves and ravines of a limestone ridge on the south portion of the island. Although the island was declared secure on 1 August, mopping up patrols continued into 1945.
Tinian became an important base for further US operations in the Pacific. North Field became operational in February 1945 and West Field in March. The Seabees built six runways for the Twentieth Air Force's Boeing B-29 Superfortress bombers. Bombers based on Tinian took part in the bombing of Tokyo in March 1945 and the atomic bombings of Hiroshima and Nagasaki in August 1945.
Background
Strategy
After World War I, the United States had developed a series of contingency plans for the event of a war with Japan known as the Orange plans. These envisaged an advance through the Marshall and Caroline Islands to the Philippines, from whence Japan could be blockaded. The Mariana Islands figured only incidentally in the plans, as they lay north of the direct route between Hawaii and the Philippines. During World War II, the islands attracted the attention of naval and air strategists. At the Casablanca Conference in January 1943, the US and British Combined Chiefs of Staff had endorsed an offensive in the Central Pacific along the lines envisaged in the Orange plans. In his formulation of the strategy, the Commander in Chief, United States Fleet, Admiral Ernest J. King, specifically mentioned the Mariana Islands as "the key to the situation because of their location on the Japanese line of communications."The Joint Chiefs of Staff envisaged the Marianas as a naval base, but another rationale for the capture of the Mariana Islands emerged with the development of the long-range Boeing B-29 Superfortress bomber. From the Mariana Islands, the B-29s could reach all the most significant industrial targets in Japan, and they could be supported by sea. The air staff planners began incorporating the Mariana Islands into their long-range plans in September 1943. The Combined Chiefs endorsed this at the Cairo Conference in December, along with a two-pronged offensive, with the Central Pacific drive in conjunction with one along the north coast of New Guinea. In response, the Commander in Chief, Pacific Ocean Areas, Admiral Chester W. Nimitz, produced a campaign plan called Operation Granite, which tentatively scheduled the capture of Mariana Islands of Saipan, Tinian and Guam for November 1944 as the culmination of the Central Pacific campaign.
By February 1944, there was consideration of advancing the Operation Granite timetable by bypassing Truk and heading directly for Palau or the Marianas after the capture of the Marshall Islands. On 7 March, Nimitz and his Deputy Chief of Staff, Rear Admiral Forrest P. Sherman met with the Joint Chiefs of Staff in Washington, DC, where they were questioned by the Chief of Staff of the United States Army, General George C. Marshall, and the Chief of Staff to the Commander in Chief, Admiral William D. Leahy. Sherman argued that the neutralization of Truk required the occupation of the Mariana Islands to cut the air route to Truk from Japan. On 12 March, the Joint Chiefs of Staff directed Nimitz to neutralize Truk and occupy the Mariana Islands.
Tinian was considered a target from the outset, Lieutenant General Holland M. Smith's Northern Troops and Landing Force was ordered to "land on, seize, occupy and defend Saipan. Then be prepared to seize Tinian on order." The American forces assaulted Saipan on 15 June. The Battle of Saipan lasted until 9 July, when the island was declared "secured". The cost was high: 14,111 of the 71,034 NTLF personnel were killed, wounded or missing in action. Mopping up operations continued until October, but preparations began immediately for the attack on Tinian.
Plans to capture Tinian were prepared concurrently with those to capture Saipan. Tinian lay only from the southern tip of Saipan, and its proximity to Saipan meant that while it remained in Japanese hands, Japanese aircraft could attack Saipan by staging though Tinian. The garrison might raid Saipan, and they could observe ship and aircraft movements on Saipan and communicate them to Tokyo.
Tinian also had value in its own right, as its flat terrain made it highly suitable for the development of air bases. There were already airfields that looked promising for development into B-29 airfields. Ushi Point Airfield was the main airfield; it had a hard-surfaced runway long. Two other airfields were in use and another was under construction: Airfield No. 3, which lay immediately south of no.1; Airfield No. 2, at Gurguan Point; and the unfinished Airfield No. 4 near Tinian Town.
Geography
Along with the other Mariana Islands, Tinian was claimed for Spain by Miguel López de Legazpi in 1565. Guam was seized by the United States in the Spanish-American War, and Spain sold the remaining islands to Germany. They were occupied by Japan during World War I and became part of Japan's South Seas Mandate. Tinian lay just from the southern tip of Saipan. It covered about, measuring from north to south, and across at its widest point. The terrain was generally low and flat, making it suitable for airfields. There were two hills in the north: the Mount Maga and the Mount Lasso. There was also a rugged limestone hill mass of cliffs and ravines in the south. About 90 percent of the island was covered in sugar cane fields. The square fields gave the island a checker board look from the air. Fields were surrounded by drainage ditches or windbreaks of trees or hedgerows.Most of the island was encircled by jagged limestone cliffs that ranged from high. There were only a few beaches, which the Americans designated by colors. The best beaches were around Sunharon Bay in the southeast: Blue Beach, south of Tinian Town, was long; Green Beach One, located between the two piers at Tinian Town, was also long; Green Beach Two, at the southern end of Tinian Town, was long; Red Beach One and Two were north of the piers, with a combined width of ; and Orange Beach, north of Red Beach One, was long.
There were two beaches on the east coast at Asiga Bay: the Yellow Beach One and the Yellow Beach Two. These were flanked by cliffs and subject to heavy surf when there was an easterly wind. There were also two small beaches on the northwest coast: the White Beach One and the White Beach Two. The small size of the White and Yellow beaches made them unattractive: a division normally required a landing beach long.
There was little seasonal variation in temperature, which ranged from an average of in January to in June, but the average humidity in those months was 78 and 84 percent, respectively. Fair weather prevailed during the dry season from November to March, but the wet season from April to November was characterized by frequent rains and occasional typhoons. Sunharon Bay was little more than an anchorage, and was unusable in rough weather.
According to a 1 January 1944 census, Tinian had a population of 18,000 Japanese civilians, most of whom worked in the sugar cane industry, and 26 ethnic Chamorro people; most of the original population had been forcibly removed to other islands. The main settlements were Tinian Town in the south and two small villages around Ushi Point Airfield in the north. The former was the administrative center of the island, while the latter housed airfield workers. The primary road network consisted of roads approximately wide and surfaced with crushed coral. They were generally straight, following the edges of the cane fields. Approximately of narrow gauge railways connected the sugar plantations with Tinian Town.