His father was Lieutenant Colonel Count Alexander Bruce, and Ekaterina Alekseyevna Dolgorukova was his stepmother.

James Bruce married Praskovia Rumiantseva, sister of General (and later Field Marshal) Pyotr Rumyantsev.

These connections greatly helped the career of James Bruce.

Even after Praskovia was banned from the court in 1779, after having had an affair with the Empress' lover, Bruce stayed in favour and received new posts.

[1] He died the same year, without male offspring, and with him ended the line of the Russian counts Bruce.