Granger was born in Suva in 1900,[1] the only son of Australian Blance (née Wadeson) and Canadian William Henry "Tavua" Johnson.[2] Growing up, he was given the nickname Tui (chief), becoming known as Tui Johnson.[3] He married Val, with whom he had five children,[2] and also joined the Fiji Defence Force, becoming a lieutenant.[4] In 1930 he was appointed German consul in Fiji.[5]
He went into business and after working at Brown and Joske, he joined W.R. Carpenter in 1937,[6] going on to become managing director.[3] He later served as chairman of the Suva Chamber of Commerce.[7]
Following the 1944 elections, he was appointed to the Legislative Council by Acting Governor John Fearns Nicoll as one of the two nominated European members.[8] In 1945 he was an acting member of the Executive Council, covering for the absent Hugh Ragg.[9] Although he was not reappointed following the 1947 elections, he was nominated to the Legislative Council again in 1953,[10] serving until the 1959 elections. He also served on Suva Town Council, representing the Muanikau ward until retiring in 1955.[11][12]
Johnson retired in 1970 and moved to Queensland in Australia.[13] He died in Australia in 1978 at the age of 78.[3]