Daniel Allison was a fourth-generation MechWarrior who grew up touring the Terran Hegemony via his mother's duty stations. Allison would attend the War Academy of Mars, first seeing services with the 135th Royal BattleMech Division in 2690 after graduation. Allison would quickly attract fame in the SLDF as an exceptional marksman and astute tactician for his prowess in hunting bandits on Hazelhurst. Coming to the attention the 135th's commander General Ellis Wilfred, in 2692 Allison was one of three MechWarriors from the 135th sent to the Military Academy of Aphros' prestigious Gunslinger Program. Daniel Allison would excel there, becoming the only trainee to defeat all of his instructors in one-on-one combat. His last match against Colonel Jack Henry Fiesta, lasted a fierce forty-eight seconds. 
Following graduation from the Gunslinger Program, Daniel Allison was promoted to Colonel and command of the 29th Royal Dragoon Regiment in 2701, also serving as the Regiment's Champion. In 2702 Allison and the Twenty-ninth were rotated to Annapolis where the House Kurita duellists had an impressive record of thirty-one wins and no losses. Allison's first duel was against Sho-sa Tomo Fukuhara, though Fukuhara fired first Allison was able to evade most of the Ronin' MechWarrior's laser and missile fire, firing two PPC shots in return, the first severing Fukuhara's 'Mech's left leg and the second breaching the ammunition magazine of Kuritan's LRM 10 and gutting his 'Mech to earn the first SLDF victory on Annapolis. Forty-two years and twenty worlds later, Daniel Allison would retire from the SLDF on his seventh-fifth birthday, having served longer than any other gunslinger, with a impressive duelling record in his BattleMaster of 59 wins, zero losses and 1 draw. 
Upon his retirement from the SLDF, Daniel Allison went to work for Kallon Industries as Vice President of BattleMech Design, which would see him working on many prestigious projects but is most often remembered as the father of the exceptionally accurate Garret D2j targeting and tracking system. 
- The Star League, p. 59, "Famous Star League Gunslingers"
- Era Report: 2750, p. 84 "Major Personas - Terran Hegemony - Daniel Allison"