John Chamberlin was born May 1845 in Ohio. He enlisted with Company I of the 23rd Ohio Infantry Regiment (Union Army) on March 15, 1864, at the age of 18. He was honorably discharged with the rank of corporal on July 26, 1865. He served under General Philip Sheridan in the Shenandoah Valley Campaign in 1864.  Chamberlin was involved in many battles, including the battle of Opequan Creek (also known as Winchester) on September 19, 1864. The last battle for his regiment was the Battle of Cedar Creek on October 19, 1864, when Sheridan and his men won the area surrounding Winchester for the Union. Following the battle, the 23rd Ohio remained stationed in this area until the end of the war. Two soldiers of the 23rd Ohio, Rutherford B. Hayes and William McKinley,eventually became United States presidents.

Following the war, Chamberlin spent some time in Pennsylvania. It was there he met his wife, Malissa, who had been born in Pennsylvania in December 1844. John and Malissa had a total of eight children, five of whom were born in Pennsylvania. The family eventually moved to Oakes, North Dakota, where John served as the town’s postmaster and police deputy. John Chamberlin died in 1914 and is buried in Oakes.