43^rd Infantry Division

The 43rd Infantry Division entered combat in the Northern Solomons, where it fought in the New Georgia campaign for Munda Airfield. The 103rd Infantry Regiment and 169th Infantry Regiment reached the outer taxiways of Munda on August 1, 1943, and the airfield fell on August 5 after prolonged and difficult fighting through dense jungle and fortified positions. The 172nd Infantry Regiment then landed on Arundel Island on August 27 against determined opposition, clearing Bobmoe Peninsula by September 20 and forcing the Japanese to evacuate the following day.

After service in New Guinea, the division joined the Luzon campaign, landing at San Fabian on January 9, 1945. The 103rd Infantry took San Jacinto the following day, and after heavy fighting the 169th Infantry took Hill 318 and the 172nd Infantry took Hill 580 on January 13. The 103rd Infantry seized the crest of Hill 600 on January 21 while attached infantry completed the Battle for Blue Ridge. The 169th Infantry fought the Battle for Hill 355 January 15–24, and the 172nd Infantry secured Rosario on January 26; the 158th and 172nd Infantry then linked up at Cataguintingan on January 27, opening the Damortis-Rosario road north from the Lingayen lodgment.

The division was later committed to the Shimbu Line east of Manila, where the 172nd Infantry battled up Sugar Loaf Mountain from March 14 and Hill 1200 fell to the regiment on April 1, turning the Shimbu Line and allowing the 103rd Infantry to secure the Santa Maria Valley. Attacking toward Ipo Dam on May 6, the division seized it intact May 14–17, critical to controlling water supply for Manila. Mopping up in the Ipo sector continued into June, followed by operations in the Wawa area.

By the end of the war, the division had moved from jungle campaigns in the Solomons to some of the most difficult mountain fighting on Luzon.