Mr John Flack was born at 16 Connswater Street in Belfast, Ireland on 18 August 1883. Coming from a Presbyterian family, he was the only child of mariner William Flack and the former Eliza Keenan. 

Flack first joined the British Army in 1900 but it is not clear if he saw any active service. By the time of the 1911 census he was living with his by then widowed mother at 28 Manderson Street, Belfast and he was described as an army pensioner and general labourer. 

John was married in Knock Presbyterian Church on 25 December 1911 to Mary Wilson (b. circa 1885); the couple had previously had a child out of wedlock, George, who was welcomed in December 1907. The couple made their home at 32 Church Street East and went on to have a further two children: son John arrived in December 1912 and daughter Mary “May” in September 1914. 

Flack’s ship prior to Titanic had been the Olympic. He joined Titanic at Belfast for the delivery trip to Southampton where he then disembarked.

In the following years Flack served during WWI. Ultimately living at 69 Brandon Parade in Belfast, John Flack died in hospital on 15 February 1961 and was buried in Redburn Cemetery in Holywood, Co Down two days later. He was survived by his wife Mary and two children.