Zed Zed Fiver Bravo Foxtrot (005BF) was taken from a Side 3 Zeon Orphanage at the tender age of 6 months, after he was given up to the orphanage at the insistence of a noble's son, who had impregnated a commoner. Zzed does not know this, as it is sealed within his records.
005BF was raised in a special training creche with other children also taken from various orphanages. His name is the code that indicates which orphanage he was taken from. The first 15 years of his life was spent in a small laboratory complex, being trained for military uses, piloting, and combat. Those that washed out of training were disposed of to keep the training experiment a secret.
By the time the complex was found out by Zeon high command (it was being run as a rogue operation as part of R&D), only 3 of the original First Creche Cadets were still alive. 005BF, 10ARK, and 0M3GA. The three children were released from their creche by the Zeon commanders, and because they knew no other life, were placed into the Zeon Mecha forces. To make it easier for them to integrate, they were given new names to answer to, based on their previous names. Zzed Fox, Ten Ark, and Zed Omega. Officially, their names are still the designations given to them, primarily because while they will answer to the alias's, they will only acknowledge their designations as their real names.
His assignment to the 206th is his first assignment. High Command decided that splitting them up would be better to increase the speed of their acclimitization to their new life.