Mr Donald Samuel Campbell (Clerk, 3rd class) was born in Geelong, Victoria, Australia in 1884.

He was the son of English parents, John Lewthwaite Campbell (b. 1829) and Ellen Day (b. 1844), his father being a native of Surrey. His maternal grandfather was the Reverend Samuel Day (1811-1908).

He had six siblings: Alice Proudfoot (b. 1870), Jessie Hetherington (b. 1879), Naomi Olive (b. 1880), John Wallace (b. 1881), Ivy Marion (b. 1886) and Eva Glover (b. 1888).

Donald lost his father in 1888 and by 1912 his mother was living in "Santon," Beaconsfield Upper in Victoria.

Campbell had worked at sea from a young age and, in 1904, was serving aboard the SS Nemesis but had disembarked at Port Pirie before that ship foundered off New South Wales in July that year with the loss of all aboard. He later served as purser aboard SS Ulimaroa, a passenger steamship operating from Sydney to New Zealand via Melbourne and Hobart.

Campbell was married in 1910 to an English-born New Zealander, Ethel May Hallett (b. 1888), a woman of ill-repute who had faced the courts on numerous occasions for theft and fraud and who was known to have used several aliases during her time. Coming from a financially comfortable family, Ethel had lost her mother at a young age and her father Thomas Richard Hallett had died in 1906, following which she was in the care of an aunt, spinster Mary Elizabeth King. She had emigrated from her native London to Auckland in 1907 aboard the SS Fifeshire with the intention of becoming a domestic maid but within a short time was charged with the theft of jewellery and soon racked up further brushes with the law for theft and fraud in Auckland and Wellington.

Donald and Ethel reportedly had a child, 18-months-old when they joined the SS Commonwealth in Adelaide on 13 April 1911. The New Zealand Herald (October 1911) reported that Ethel, then a resident of South Side, Clapham had obtained £150 by false and fraudulent pretences from a Mrs Mary Elizabeth Foote of Auckland whilst on their journey to England aboard the Commonwealth, aboard which her husband was serving as purser. The article also states that Ethel had presented herself as the daughter of the former Lord Chief Justice of England, Sir Richard Hunter and was headed back to England to take over property and a sizeable remuneration following his death. She was found guilty on 15 September and sentenced to seven months imprisonment and would have still been serving out her sentence at the time of the Titanic disaster. What became of their child, if indeed there was one, is not known.

When he signed-on to the Titanic, on 9 April 1912 the only address Campbell gave was "White Star Line, Southampton". His last ship had been the Ulimaroa and as a third class clerk his monthly wages were £5.

Campbell died in the sinking and his body, if recovered, was never identified. The New Zealand Truth (18 May 1912) reported:

"The Titanic disaster claimed as a victim Donald Campbell, one-time purser on the Ulimaroa, who sprang into prominence because he married May Hallett. Campbell was assistant purser on the Titanic, and his life was offered up as a sacrifice. Incidentally, May should now be nearing the end of her seven months' stretch. Will she prove a Merry Widow?"

Ethel would continue to be mentioned in New Zealand media for years to come and the loss of her husband Donald was at one point accidentally attributed to the Lusitania disaster. What became of Ethel May Hallett Campbell in later years is not certain; her death was reported in the New Zealand Observer in May 1922 but her final movements are vague. Donald's mother Ellen died in Victoria in 1921.