James was born on the 27th of July 1860, in Limerick, Ireland, and I am unsure of when he emigrated to the US, mostly because his name is a very common name around that time of those traveling from Ireland. I did find a record of that could have been James arriving at Ellis Island in 1871, but I am not certain. What is certain is that he enlisted in the US Marine Corps on the 19th of August 1889, and he was deployed to China in support of the Boxer Rebellion. It was his actions there as a Private that would later earn him the Medal of Honor. The citation reads:

In the presence of the enemy during the battle near Tientsin, China, 13 July 1900, Cooney distinguished himself by meritorious conduct.

James received the Medal on the 24th of January 1902, and a little over a year later, of the 14th of March 1903, Corporal James Cooney died at the age of 42. He is buried in the Mare Island Cemetery in Vallejo, California: Section D, Row 10, Plot 093.