Longinus – called Longo for short – and his two brothers Cletus and Loftus were natives of the Jewel City of Beryl who joined the Black Company in Shadow Games. They quickly established themselves as indispensable engineers, artillery specialists, and architects. They served the Company with distinction, especially during the Siege of Dejagore (Bleak Seasons) and the rest of the Shadowmaster wars (She Is The Darkness).
All three brothers became members of the Captured. This was an ordeal which Longinus, unlike his brothers, would not survive.
Shadow Games
Longinus, Cletus, and Loftus and were serving in the Urban Cohorts of Beryl in Shadow Games. Without warning, the giant warship called The Dark Wings arrived at Beryl's harbor. Croaker, with his handful of Black Company brothers and the Lady, rapidly passed through the city. The three brothers recognized the Company from the band's service there (the events of The Black Company) during the brothers' younger years, which was when Beryl was independent and not yet part of the Lady's Empire. They deserted the Cohorts, and, with Murgen's sponsorship, were all admitted into the Company.
She Is The Darkness
In She Is The Darkness, Longinus and his brothers improved Lady's original design on her fireball projectors exponentially. They vastly improved the infantry models and also created incredibly accurate cannon-sized versions. They would help the Company defeat and capture Longshadow at the Siege of Overlook, ending the Shadowmaster wars in victory.
After that, Longinus and his two brothers traveled with Croaker, Lady, Murgen and about 44 others during the Company's historic passage through the homeworld shadowgate and onto the Plain of Glittering Stone. At the Fortress With No Name in the center of the Plain, the three brothers were doomed to become members of the Captured, a group that was imprisoned by Soulcatcher within the Cave of the Ancients in a magic stasis for at least 15 years.
Water Sleeps
At some unspecified point during the Captivity, in the 15-year gap between She Is The Darkness and Water Sleeps, Cordy Mather was somehow freed of the sorcery. Mather unintentionally killed Longinus, Wheezer, Candles, two Nyueng Bao bodyguards, and two Shadar soldiers by physically moving them without the necessary sorcerous precautions.
When Sleepy finally reached the Captured after her arduous quest at the end of Water Sleeps, she stated that she saw Cletus among the 7 deceased men who had been accidentally killed by Mather. However, later events would reveal that she misidentified Longinus's corpse as belonging to Cletus. Longo's surviving brothers, Loftus and Cletus, continued to serve the Company but would both be killed during the costly Battle at the Shadowlander cemetery in Soldiers Live.