John was born on the 28th of October, 1877 in Germany and he was a Gunner's Mate Third Class shortly after entering the US Navy. It was his actions during the Spanish-American War that would earn him the Medal of Honor. The citation reads:

On board the U.S.S. Marblehead, during the operation of cutting the cable leading from Cienfuegos, Cuba, 11 May 1898. Facing the heavy fire of the enemy, Davis set an example of extraordinary bravery and coolness throughout this action.

When John Davis died on the 9th of June, 1970, he was the last living recipient from the Spanish-American War. He is buried in Arlington National Cemetery: section 11, lot 639-SS.