Russell J. Nelson 101st Infantry Regiment is military unit and formation activated by Philippine Army during the early days of World War II.

It was composed of Filipinos who resided in Mindanao, few officers from Luzon, Moros, and American soldiers assigned to command and train the regiment.

1st Battalion under the command of Captain Abellana with its military instructor Major John H. McGee was sent to Del Monte field to secure it.

Lieutenant Felipe, Ong ping, and Avis are officers of engineer detachment attached to the regiment Made invaluable service.

On August 28, 1941 to December 1941 1st Battalion was commanded by Captain Abellana with Major John H. McGee as its senior instructor, it was posted in Tankulan to guard Del Monte Field for time being it was the only combat unit in Cagayan sector until January 1942 when it bolstered with the transfer of 61st & 81st Field Artillery Regiments.

2nd Battalion was commanded to Captain Nicolas Gabutina with its senior instructor Lieutenant Colonel Roger Hilsman Sr., when it was ordered to moved to Davao and Major Frank McGee, (Ret.)

On December 10, 1941, General Vachon the 101st Division and Davao-Cotabato sector commander ordered Lieutenant Colonel Roger Hilsman Sr., to bring 2/101st Infantry under Captain Gabutina to Davao City and setup defense against Japanese invasion.

Along with 2/82nd Infantry under 1Lieutenant Luis Jakosalem who came from Cebu, Davao PC Battalion under Major Gregorio Ferreols, and some volunteers that his force reached more than 2,000.

They undertook 15 days hiking through the thick jungle trek and deep ravine eating corn, monkey meat, and bananas.

After losing contact with Hilsman, General Vachon sent Lieutenant Colonel Howard Frissell to Digos along with 1st Battalion 101st Infantry and 1st Battalion 101st Field Artillery, setup defenses in Digos area to prevent Japanese from reaching Kabacan the southern terminus of Sayre Highway.

[5] 2nd Battalion 101st Infantry now under Major John Richardson was brought to Makilala from Kabacan to prevent Japanese infiltrating from the jungles of Padada.

They run and hide to the hills, mountains, and jungles waited for the guerilla units to get organized and joined at the earliest opportunity.