Elizabeth Lochley became the commanding officer of Babylon 5 in 2262, replacing her ex-husband John Sheridan as CO of Babylon 5 when he assumed the Presidency of the Interstellar Alliance. Personally chosen by Sheridan as his replacement, the two knew each other from his days at the Earthforce Academy, and as such he felt that she was capable of dealing with the kind of problems that would arise on Babylon 5.