On 24 August 1943 the Battalion was re-designated and activated as the 2nd Battalion, 20th Marines, (Engineers), 4th Marine Division. 28 February 1944 saw the battalion in action at Kwajalein and Majuro Atoll in the Marianas Islands. As 1943 progressed the unit participated in the assault and capture of both Saipan and Tinian. For its actions, the Battalion was awarded the Presidential Unit Citation. The Battalion was again re-designated on 1 September 1944 as the 4th Pioneer Battalion, 4th Marine Division and assigned to the 25th Regimental Combat Team as shore party for the assault on Iwo Jima. There the Battalion was awarded the Navy Unit Commendation. A Co, B Co, and C Co. were awarded the Presidential Unit Citation individually for being attached to Assault Battalions. On 31 March 1945, the 4th Pioneer Battalion re-deployed to San Diego, California. The Battalion was awarded the Asiatic Pacific Campaign Streamer with four bronze stars and the World War II Victory Streamer for service throughout World WarII. Ppl