Alexander Barthauser was an admiral of the Reuenthal Fleet. Commanding a small fleet of 2,400 ships, Fleet Admiral Oskar von Reuenthal would put Barthauser's unit into action when a small force could potentially change the course of the battle. He fought at the Battle of the Corridor and the Second Battle of Rantemario in 800 UC. On 7 December 800 UC, after the Second Battle of Rantemario, the Reuenthal Fleet was fired upon by its supposed allies in the Grillparzer Fleet. Barthauser's headquarters could not be raised by the Tristan after the opening salvo.