'Taxpayer' was the US geographical rather than operational codename for Angaur island, which was taken from the Japanese during the Pacific Ocean campaign (17 September/22 October 1944).
This battle was part of the larger 'Forager', which lasted from June to November 1944, and 'Stalemate II' in particular.
Formerly known as 'Domesday', Angaur is a tiny limestone island, just 2.25 miles (3.6 km) long, 1.5 miles (2.4 km) wide and extending to some 2,000 acres (810 hectares) of generally rolling terrain except in the north-western corner, which is characterised by three small lakes and otherwise comprises a number of very rugged limestone and coral ridges up to 200 ft (60 m) high resulting from the strip-mining for phosphate. The most southerly island of the Palau islands group, Angaur is separated from Peleliu to its north-west by a 7-mi (11-km) strait, and was a site of phosphate mining. In the middle of 1944, the Japanese had 1,400 troops on the island, under the overall control of the Palau Sector Group's commander, Lieutenant General Sadae Inoue, and under the local command of Major Goto, who was stationed on the island.
The weak defences of the Palau islands group and their potential for airfield construction made them attractive targets for the Americans after the 'Cataract' capture of the Marshall islands group, but a shortage of landing craft meant that operations against the Palau islands group could not begin until the Mariana islands group had been taken in 'Forager'.
It was planned that after the 'Stalemate II' assault on Peleliu was well established, Major General Paul J. Mueller’s 81st Division would land the 322nd Regimental Combat Team on the northern Beach Red, and the 321st RCT on the eastern Beach Blue.
A bombardment of Angaur by the battleship Tennessee, four cruisers, and 40 Douglas SBD Dauntless dive-bombers operating from the aircraft carrier Wasp began on 11 September. On 17 September, Major General Paul J. Mueller’s US. 81st Infantry Division landed on the north-eastern and south-eastern coasts. Both of the two landed RCTs were counterattacked during the night, but advanced and linked in the course of the following day. By the end of 19 September the main area of continued Japanese resistance lat to the north-east around Romauldo Hill, so the 323rd RCT was sent to Ulithi.
Resistance stiffened as the US force advanced on 'the Bowl', a hill near Lake Salome in the north-west of the island and he point at which the Japanese planned to make their last stand, after the rest of Angaur and Saipan town had been taken. There was another small position where the Japanese had about 400 men in a defensive position at the south-eastern corner of the island, around Beach Green, and this was overcome on 20 September after two days of severe fighting which cost the Americans some 300 casualties.
From 20 September, the 322nd Infantry repeatedly attacked 'the Bowl', but each time the 750 defenders drive them back with artillery, mortars, grenades and machine guns. The combination of hunger, thirst, artillery fire and bombing gradually took their toll on the Japanese, and by 25 September the Americans had penetrated into 'the Bowl'. Rather than commit themselves to any necessarily costly fight for possession of the caves, the Americans used bulldozers to seal the entrances. By 30 September, the island was said to be secure despite the fact that the Japanese still had about 300 more men in 'the Bowl' and surrounding areas, and these held out for almost four more weeks. Toward the end of the first week of October, the protracted conflict had became one of minor patrol actions in which extensive use of sniping, ambushing and extensive booby-trapping by each side.
Goto, the Japanese commander on the island, was killed on 19 October in fighting to keep possession of a cave, and the final day of fighting was 22 October after 36 days of fighting and blasting the Japanese resistance from their caves with explosives, tanks, artillery and flamethrowers.
Airfields were being built even as the battle was being fought, but the delay in the start of the Palau islands operation meant that the airfields were not ready in time for the start of the 'King II' landings on Leyte island in the the Philippine islands group from 20 October. Admiral William F. Halsey, commander of the 3rd Fleet, had argued before the invasion of the Palau islands group that the operation was unnecessary, and historians have agreed with him, suggesting that the main benefit was the combat experience gained by the 81st Division.
During the fighting, 'Seabee' construction personnel built an airstrip to accommodate the Consolidated B-24 Liberator heavy bombers of the 494th Bombardment Group, 7th Army Air Force. The group engaged in frequent bombings of the Philippine islands and others of the Palau islands group.
The 81st Division moved on directly to the 'Stalemate II' battle for Peleliu island in support of Major General William H. Rupertus’s 1st Marine Division, which was encountering very
fierce resistance in the central highland of that island. The division remained on Peleliu for another month, taking the island and consolidating.