|The following is based on Fallout Tactics and some details might contradict canon.|
Around 2197, the Brotherhood of Steel's Fang Squad encountered a large contingent of heavily armed super mutants in the region of St. Louis. They fought against this overwhelming force and managed to radio in a distress call right before they were annihilated. Eight battle-hardened squads led by General Simon Barnaky rushed to the scene and engaged in pitched combat with the super mutants.
Near the end of the battle, General Barnaky, Burke and another warrior were all that was left of their squad. They were confronted by Toccomatta and his super mutants. While Barnaky and the other warrior engaged their overwhelming enemies in combat, Burke hid behind them in a trench line, scared of being killed. The other warrior was killed (or possibly taken prisoner, since his body is not found near the site of the battle) and while the super mutants were taking Barnaky alive, he shouted to Burke for help, and while Barnaky's captor was in line of fire, Burke didn't shoot. He didn't hide successfully, however, as soon he was found by a super mutant who attached a C4 to him while laughing.
While the Brotherhood was able to push them back initially, its losses were staggering. As a result, they needed to pull their forces out of there.
At General Barnaky's request, the squad led by the one later known as the Warrior was sent to rendezvous with his mobile command center and execute the evacuation of the wounded Brothers. There were three groups to be evacuated, including the one led by General Barnaky, but only one, led by Paladin Emerald Solo was evacuated. All others were killed, with only Barnaky, who was taken prisoner by the super mutant High Inquisitor Toccomatta, and Burke, who lived long enough to meet the Warrior, survived the slaughter.
The Battle of St. Louis appears only in Fallout Tactics.