Johan was born in Sweden on the 12th of May, 1870 and he enlisted in the US Navy in New York. He was an Ordinary Seaman during his deployment in support of the Spanish-American War and his actions earned him the Medal of Honor. The citation reads:

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

Johan Jacob Johansson received his Medal of Honor on the 7th of July, 1899 and he died on the 4th of December, 1948 at the age of 78. He is buried in Arlington National Cemetery, although his headstone has his first name as Jonah and his last name spelled with two Ns and one S: Section 13, Lot 720.