The 23rd Regiment was mustered into federal service in the Union Army on 18-25 June 1863, assigned to 1st Division, VI Corps, Department of the Susquehanna.
When the regiment arrived in France, it had a strength of 3,003 officers and enlisted men, and it was moved into the front lines on 25 June 1918.
On 31 August 1918, the Ypres-Lys Offensive began, and the 106th Regiment was engaged in the reconnaissance efforts prior to the main battle.
Alongside the 53rd Brigade and the rest of the 27th Division, the 106th attacked German position in the Second Battle of the Somme from 24 September to 21 October 1918.
The desperate fighting is clearly demonstrated by the actions of Lieutenant Colonel J. Leslie Kincaid, the Judge Advocate of the division staff.
From 25 to 28 September, Kincaid took command of a leaderless battalion of the 106th Infantry and managed to hold off an enemy counterattack by organizing every man in the battalion including runners, cooks, signalmen, etc., in the defense; he even personally manned a Lewis gun during the action.
[5][6] On 1 September 1940, the Headquarters and Headquarters Detachment 3rd Battalion, Service Company, and Companies C, G, and L were converted and redesignated as the 101st Military Police Battalion, while the remainder of the regiment was converted and redesignated as the 186th Field Artillery Regiment.
On 29 May 1898, it was mustered into federal service for the Spanish–American War, consolidated with other units, and redesignated the 1st New York Volunteer Infantry.
The regiment served at various forts in Hawaii and the continental United States before being mustered out of service from 20-26 February 1899.
The 10th New York reported for duty during the Pancho Villa Expedition, but was never officially mustered into federal service and returned to home stations.
The 2nd Battalion (2-106), occupied Majuro Atoll on 1 February 1944, against no resistance, and remained there until it was sent to Oahu for training on 5 March 1944.
The regiment consolidated its three battalions in Hawaii on 13 April 1944, and landed on Saipan on 20 June 1944, five days after the initial invasion.
The 106th fought along rough jungle terrain at the base of Mount Tapotchau, which they dubbed "Purple Heart Ridge[13]" and "Death Valley."
After many of the Japanese strongpoints had been subdued, the defenders launched a second last ditch Banzai charge, which the 106th was active in defeating.
The regiment departed Espirtu Santo for Okinawa on 20 March 1945, and participated alongside the XXIV Corps general attack on the island.
Working together with the 105th Infantry Regiment, they fought to capture a hill called The Pinnacle, a tall spire of rock, where the Japanese had prepared an intricate defense.
The last action of the 106th Infantry's World War II chronicle occurred when 1-106 repelled a Banzai charge west of the Pinnacle on 22 April 1945.