Following the war led by a Jedi-Republic Coalition against the Mandalorians, and the rise of the New Mandalorian government, Aka'liit (or the Mandalorian Faithful in Galactic Basic Standard) was formed by those within the Mandalorians whom desired to stay true to their warrior past.
The Faithful created a secret network of clan representatives, passing down the Resol'nare and Mandalorian history to their children. Within a generation, the Faithful appointed the first in their line of 'True Mandalores', whom they offered their allegiance to secretly. The Faithful referred to this time as ba'slan shev'la, choosing to disappear and prepare for an opportunity to strike back against the Faithless, calling their warriors Alor'a Aka'liit (the Vanguard of the Faithful.)
In 200 BBY, the Faithful began to consider the machinations of the Ithullan to be a threat, prompting a crusade against the their world. The near extinction of the Ithullans did not sit well with all of the members of Aka'liit however, and was regarded as the beginning of the division that would lead to the split between the True Mandalorians and the Death Watch.
The split within the Faithful was finally realized upon the choosing of Jaster Mereel as Mandalore, as his vision of the Mandalorians as merely highly paid soldiers, did not sit well with those who would become the Death Watch.
- The Bounty Hunter Code: From the Files of Boba Fett (First appearance)