Mr William Cahoone Johnson Jr was born in Newark, Essex, New Jersey on 1 October 1892.

He was the son of William Cahoone Johnson (b. 1856), a bank clerk, and Amy Belmont Rogers  (b. 1868), of New York and New Jersey respectively, who had married on 1 October 1885. He had only one known sibling, his elder sister Bessie (b. 17 March 1888).

William Cahoone Johnson as an adolescent

William moved to Hawthorne, Passaic New Jersey around 1899 and he and his family appear in that town on the 1900 and 1910 census records. His first job was in the Wells Fargo company in their New York offices. He entered the marine service as a cadet on the American Line's St. Paul around 1910 on which he was advanced rapidly through the ranks and was transferred to the SS Philadelphia around 1911, serving as fourth quartermaster. By 1912 William Johnson lived at Diamond Avenue, Hawthorne and continued to work for the American Line aboard the Philadelphia. He was a member of the local YMCA and a member of the Young People's Club and Young Men's Club, both of Hawthorne.

William Cahoone Johnson, standing centre

The British coal strike caused scheduling problems and Philadelphia's westbound voyage was cancelled, with William and several other shipmates; Andrew Shannon [Lionel Leonard], Alfred Johnson, William Henry Törnquist, Alfred Carver and Thomas Storey) forced to travel aboard Titanic as passengers. William and his shipmates boarded the Titanic at Southampton as third class passengers (ticket number 370160). All the men perished and Johnson's body, if recovered, was never identified.

The fact that William was travelling under a pass ticket on Titanic caused confusion as to his survival, his name not initially appearing on the lists of the save or the dead. His distraught father placed ads in local newspapers to ascertain the whereabouts of his son. George Bolt, then manager of the Waldorf Astoria, sent word to Mr Johnson that he had in his employ two former stewards of the Titanic, one of whom, William Henry Törnquist, was also a steward on the Philadelphia and who knew young William well saw him during the Titanic's final hours:

"I knew Johnson well when I was on the Philadelphia and when he shipped for home on the Titanic. I was well pleased to have his company, as he was a fellow anyone would like.

When we were on the Philadelphia he made many friends, not alone among the crew, but among the officers as well. His sterling character was admired by all and it was this that caused him to rise so quickly in the service.

In all, I think, he served only two years, yet he was a quartermaster and still on the road to rapid promotion. Chief Officer Candy, of the Philadelphia, thought there was no one like Billy... On the Titanic the officers took to him right away, and especially the captain, who called him "Kid" and used to joke and talk with him.

When the ship struck Billy was sleeping, but arose with the rest of us and went on deck. When the lifeboats were being lowered one of the officers recognized Billy and told him to do duty at the boat, I and another steward were detailed to row in that lifeboat. Johnson never wavered, but jumped right into the work of getting the women and children safely on board of the lifeboats.

Just as the boat I was in was about to be lowered, I called to Billy and told him to climb in, as I thought there was room. The captain at the time was rushing past and he turned and, seeing Billy, placed his hand on his shoulder and said: "Jump in, Kid, you might as well have a chance..."

William Johnson reportedly refused a place offered him in the lifeboat until all the women and children were cleared.

His family continued to live in Hawthorne; his mother passed away in 1929 and his father sometime after. His sister Bessie remained a spinster for many years before eventually marrying a man named Ernest Lucas (b. 1877). She died in Passaic, New Jersey in 1981 aged 93.