Holy Chosen are fighters for the Holy Nation that can be found on the front lines against the United Cities. If certain World States are achieved, they can be found counter-attacking the Shek Kingdom. Holy Chosen can be found patrolling in large numbers making up the bulk of the army alongside a few more experienced Holy Sentinels and Paladins.
Based on their appearance and weapons, Holy Chosen appear to be Holy Servants that have been "chosen" to serve on the front lines. They possibly also include volunteering crusaders and conscripted townsfolk and peasants.
Holy Chosen may be on the path to become Holy Sentinels, taking this period to familiarize themselves with the Combat Cleaver, a Sentinel's weapon of choice. Still, their lack of armour and limited swordsmanship results in them having a very low life expectancy, so they are mostly just cannon fodder in practice. Since Holy Servants, and by extension most of the Chosen are likely slaves, this weeding out process may be intentional.
They wear [Shoddy] armour (5% chance of [Standard]) and have weapons manufactured by Unknown and Ancient.
The Statistics here are taken from FCS. Skills will be multiplied by the racial multiplier. Players should also be aware that non-player characters also level up while fighting.