A mobile suit veteran who participated in the first stage of the One Year War, the One Week Battle. During Operation British, Lt. Schmitzer was badly wounded, and forced to retire his post. The person who wounded him was none other than Ensign Agar, who later develop a rivalry with the Fenrir Corps and would subsequently end up piloting the Gundam Mudrock. However, he would go on to approach Kycilia Zabi to propose the formation of a special mobile suit task force that would become the Midnight Fenrir Corp.

The first operation he oversaw as the commander of the Fenrir Corps was the descent operation to capture an Earth Federation air base in North America. Because of supply issues, he could only send out MCPO. Austin's Zaku I A squad and Lt. Roher's Zaku II squad. The operation was a huge success. Not only did the Fenrir Corps capture the base, they also destroyed a Big Tray land warship and recaptured several MS-06 Zaku II's possessed by the Federation. Following that operation, Schmitzer oversaw the Fenrir's operation to capture California Base and its sub dock and command center. He was on hand in Seattle when Capt. Garma Zabi was betrayed by Char Aznable. However, if he knew anything of the betrayal, he never said anything. Following the death of Garma, he was re-deployed with his unit to the European front in order to try to slow the Federation advance on Odessa. Following the fall of Odessa, he retreated along with the rest of the Zeon forces. The Fenrir participated in the ill-fated invasion of Jaburo and later, the defense of California Base. After the fall of California Base, the Fenrir and Schmitzer fled to Africa, where they saw the end of the War. While it is confirmed that he survived the One Year War, it is unknown if he remained with the Republic of Zeon or fought with the Delaz Fleet during Operation Stardust or if he retired from military service altogether.

He is known to have been injured during the One Week Battle or the Battle of Loum. It is stated that his injuries were too severe for him to continue piloting MS in combat. However, as we only see his head and shoulders, it is not known what the exact nature of his injuries were.
Can no longer participate in combat, but still can pilot a mobile suit and often does in training missions with the Fenrir.
His personal mobile suit is a MS-05S Zaku I painted white and light green. It has a sound analysis system as it sensor due to the fact that he has poor eyesight.