James Richard Dinenage was born in Southampton, Hampshire, England on 3 January 1863. He was the son of William Henry Dinenage (1833-1917) and Jane Breeze (1834-1921). His father hailed from Bristol and his mother from Liverpool and they were married in Southampton in 1850.

James had ten known siblings: William Edward (b. 1851) Samuel (b. 1854), Florence Sophia (b. 1856), Richard (b. 1858), Annie Elizabeth (b. 1860), Emily Jane (b. 1866), Robert Napier (b. 1868), Amiable Louise (b. 1870), Frederick Shah (b. 1873) and Edgar Breeze (b. 1881).

James first appears on the 1871 census when he and his family were living at 13 Clifford Street, St Mary, Southampton and his father was described as an accountant. James is absent from the 1881 census when his family were living at Lichfield Road, Walsall, Staffordshire.

James was married around 1887 to Alice (Hallis) Goulden (b. 1869 in Southampton). Together they would have three children, with one surviving infancy, Richard John (b. 12 November 1891).

On the 1891 census James is absent, but his wife is resident at Clifford Street, St Mary, Southampton. He would be absent again by the time of the 1901 census. On the 1911 census James is again absent, but his wife and son are listed as living at 4 Cawte Road, Shirley, Southampton and his wife is described as the wife of a ship's steward. His son Richard was listed as a law clerk.

When he signed-on to the Titanic, on 4 April 1912, James gave his address as 4 Cawte Road, (Southampton). As a first class steward he received monthly wages of £3 15s. His last ship had been the Oceanic.

Dinenage died in the sinking. His body, if recovered, was never identified. The following death notice appeared in the Southern Daily Echo (30 April 1912) and the Hampshire Independent (4 May 1912):

DINENAGE--April 15th, on the s.s. Titanic, James Richard Dinenage, the dearly beloved husband of Hallis Dinenage, of 4, Cawte Road, Freemantle, Southampton. Deeply mourned by his sorrowing wife and son. "Gone from our sight, and to memory ever dear."

James' widow Hallis never remarried and later lived in Baddesley, Hampshire where she died on 23 December 1946, leaving her estate to her son.  His son Richard later worked as a carpenter. He died in 1974 in Romsey, Hampshire.

James' great-nephew is UK TV personality Fred Dinenage (b. 1942 in Birmingham, son of Aubrey Dennis Dinenage, b. 1909, son of Edgar Breeze Dinenage, James' younger brother).