Multiple realities(covers information from several alternate timelines)
John Schoolcraft was a Starfleet officer in the 24th century. His serial number was BV-215-4710 EZH.
In 2371, he was a crewmember aboard the USS Voyager. He was among the crew stranded in the Delta Quadrant, when Voyager was forcefully brought there by the Caretaker.
His name was listed on the crew roster display read by Harry Kim in early 2372. (VOY: "Non Sequitur")
This character was only mentioned in writing.