William was born on the 5th of January, 1871, in Newark, New Jersey and joined the US Navy in 1892. He was a Chief Carpenter's Mate when he was deployed to China to serve in the Boxer Rebellion and it was his actions that would earn him the Medal of Honor. The citation reads:

Fighting with the relief expedition of the Allied forces on 13, 20, 21 and 22 June 1900, Hamberger distinguished himself by meritorious conduct.

William received his Medal of Honor the following year and went on to also serve in the Occupation of Veracruz. He remained in the Navy until 1932 and retired at the rank of Lieutenant Commander after forty years of service. William Francis Hamberger died on the 1st of September, 1937 at the age of 66 and is buried in Arlington National Cemetery: Section 6, Grave 9164, Grid T 18.