In the early days of the Legion, the powerful Twisted Hairs tribe of Arizona would aid the Legion as scouts. Under the combined leadership of Caesar and Graham, the latter of whom had been declared the 'Malpais Legate,' the newly-formed 'Legion' led campaigns against other tribes, forming a fanatically loyal army of assimilated warriors. He crowned himself 'Caesar' and decreed that all peoples under him would set aside their old identities and embrace his vision of a society modeled after the ancient Roman Empire.

As his confederation grew, Sallow saw the need to dispose of the divisive tribal cultures. Under his guidance, the Blackfoots not only defeated but subjugated the neighboring tribes and came to regard Sallow as their one and only chieftain. Unwilling to leave his and his comrades' fate up to chance, Sallow instructed his captors in the arts of war, drawing largely on what he had read about the military tactics of Ancient Rome. While still a captive, Sallow noticed the Blackfoots' martial ineptitude and feared that their more numerous enemies would soon overwhelm them.

Not long into their travels, the group was captured by the Blackfoot tribe and held for ransom. The group included Followers Edward Sallow, Calhoun, a physician, Mormon missionary Joshua Graham, a specialist in tribal dialects. In the year 2246, the Followers of the Apocalypse sent a group to the Grand Canyon to study the region’s tribal languages.

New vegas enclave commander