A.J. Ryan was a Major in the US military and Steve Tanner's CO when he was stationed at Burtonwood.
In June 1967, when Steve got engaged to Elsie Tanner, a British national, Elsie was required to meet with the Major to obtain his permission to marry Steve. Expecting a lengthy interrogation, Elsie brought along her birth certificate and divorce papers, but in the event these were not required and Ryan only asked her a few questions relating to her previous marriage, children, and her impression of America due to her intention to reside there. Elsie was embarrassed to admit that she had been married when she first met Steve during the war and feared that it would prejudice him against her. Later, on an impatient Elsie's orders Steve checked in with Ryan to see if he had decided to approve the marriage but was swiftly dismissed from his superior's office. The Major subsequently ruled in favour of the union, with the news reaching Elsie and Steve at the Rovers via a phone call from Ryan's clerk, a Corporal who was a friend of Steve's.
Four months later, Ryan was contacted by Steve Tanner who was requesting to be transferred to Germany. Major Ryan went to Weatherfield to meet Steve. While in Weatherfield he had an argument with Ken Barlow over the violence in Vietnam.
In 1970 he sent Gregg Flint and Gary Strauss to Weatherfield to find Joe Donelli. Gregg and Gary met Major Ryan at Burtonwood and told him that they didn't know where Joe was. Later on Joe held Minnie Caldwell and Stan Ogden hostage. Eventually though Joe killed himself.