Harold Lincoln Berg was born June 1, 1914 in Winnipeg, Canada. It is unknown who his biological parents were, but the 1930 census found 15-year-old Harold living in Copley Township, Clearwater County, with his adoptive parents Ludvick (Ludvig) and Anna Berg. The Bergs were quite elderly at the time with Ludvick being 81 and Anna age 74. The owner of the farm on which they all lived was Anon Bertinius Berg, age 49. The census states that Anon is the brother of Harold. Ludvick, Anna and Anon all immigrated to the U.S. from Norway in 1906 coming into the U.S. via Winnipeg, Canada and landing in Superior, Wisconsin where Ludvick had a cousin.

The family lived in Duluth for a time before Ludvick bought a farm in Copley Township. He and Anna resided there until their deaths in 1934 and 1939 respectively. They are buried in Emmanuel Cemetery.

When he reached adulthood, Harold completed two years of college, then found a job in International Falls, Koochiching County, Minnesota where he was the circulation manager for a newspaper. He roomed with Mary and Lucille Kroll in the city for several years. He was age 26 when he registered for the draft on October 16, 1940. He listed his employer as Don Chase, Border Publishing in International Falls. Draft registrations required the writer to list someone who would always know their address. Harold listed Spencer Larson of Bagley. His brother Anon went to work in California to help the war effort.

Harold enlisted in the Army 8 JUN 1942, in Milwaukee, Wisconsin. He later received an officer commission and became a distinctive member of the OSS. The Office of Strategic Services was a wartime intelligence agency of the United States during World War II, and a predecessor of the modern Central Intelligence Agency (CIA).

Harold was a member of Detachment 101 of the OSS, which operated behind enemy lines in Burma.

Lieutenant Berg served in Burma with the famous Merrill's Marauders jungle warfare unit that traversed some of the most difficult terrain and endured some of the harshest conditions in the world to attack Japanese strongholds. In August 1944, the Marauders completed their final mission, the capture of the strategically essential airfield and settlement at Myitkyina. Shortly afterward, Lieutenant Berg joined OSS Detachment l O 1 and was assigned to a British led unit drawn from Kachin villages in the area. While leading a raid on a Japanese force on December 18, 1944, he received a burst of machine gun fire to the chest. His body could not be recovered before his unit retreated under heavy fire.