James, better known as Jimmy, was born in Liverpool in 1882, son of Eugene McGann (c. 1859 - 1910) a sailor, and Mary Kelly (c. 1861 - 1909). He had a younger brother, Joseph who was born in 1884.  

In the 1901 census he was listed a s a boiler scaler and after losing both his parents within a year. When he signed for the Titanic he listed his previous work as a trimmer on the ship the South Africa. 

Jimmy escaped on collapsible B, the lifeboat that was upturned as they attempted to launch it. He was suffering from severe frostbite when he was taken aboard the Carpathia and was hospitalised in New york upon his arrival. While there he gave a brief interview which was printed in multiple American newspapers. His words were also printed in The Yorkshire Post on April 23, 1912:

"When the water reached Captain Smith's knees, and the last boat was at least 20-feet from the ship, I was standing beside him. He gave one look all around, his face firm, and his lips hard set.

"He looked as if he might be trying to keep back the tears, as he thought of the doomed ship. I felt mightily like crying myself as I looked at him. Suddenly he shouted. 'Well, boys, you've done your duty, and done it well. I ask no more of you. I release you. You know the rule of the sea. It's every man for himself now, and God bless you.'

"Then he took one of the two little children who were on the bridge beside him. They were both crying. He held the child, I think it was little girl, under his right arm and jumped into the sea.

"All of us jumped. I jumped right after the captain, but I grabbed the remaining child before I did so. When I struck water the cold was so great I had let my hold of the kiddie."

McGann's evidence cleary contradicts the established narrative regarding the fate of captain Smith and he was not called to give evidence in either the US or British enquiries. He returned to Liverpool and is understood to have continued to work at sea.

He married Catherine McMeal (1885 - 1958) in 1914 in Liverpool and they had a son named Joseph (1915 - 1921) and a daughter Catherine (1918 - 1973). Sadly Jimmy was never to meet his daughter as he was admitted to a sanitorium with tuberculosis and died at just 34 years of age, before she was born. 

The family name might sound familiar though, His younger brother, Joseph, served in the Great War and then married Elizabeth Walls in 1918, with whom he raised his family until his death in 1962. Four of their grandsons, born to their son Joseph would become actors. Joe McGann (b. 1958), Paul McGann (b. 1959), Mark (b. 1961) and Stephen (b. 1963). It was Paul who was to become the most famous of them all, appearing in films such as Withnail & I (1987), Alien 3 (1992)  and probably best known as the 8th Doctor in long running British TV institution, Doctor Who. Perhaps his most poignant role was playing Sir Rufus Isaacs in the TV Movie Save Our Souls: The Titaanic Inquiry (2012). The actor recently narrated accounts of personal stories of those aboard the Titanic  for the Short History of podcast. You can listen to that here.