Roscaithrera are armed with a local version of the celtic longsword, soliferrum javelins and protect themselves with an iron montefortino helmet and a caetra shield.
Expert at Hiding in Forests
(Kal-ay-kay Ros-ket-rar-ah; "Callaeci Caetra-Bearers") - These men are practically the finest warriors the nobility of the Callaeci tribes can muster. Equipped with the best weapons the region has to offer - multiple soliferra all-iron javelins and a local development of the ubiquitous Celtic longsword - they are certainly good medium infantry, and a match for any warrior in their class, even if a bit lightly protected with just an iron helmet and a caetra shield.
In times of peace they practice a kind of armed dance, similar to those practised in Britannia, which require a great deal of dexterity to do properly, effectively training them for combat. In war they march at an even step, and then raise a battle-song as they charge on their foe. Also, the rugged terrain of the Callaeci homeland means they are also used to skirmishing tactics in addition to more linear warfare, so while they are at a disadvantage against heavier enemies, in a straight fight they can use their versatility to even up the odds.
Historically, the Callaeci were a brave and numerous group of tribes that made their home North of the Lusitani, across the river Douro. They arrived during the period of Celtic migrations, displacing or conquering existing cultures, and carved up kingdoms for themselves in an area roughly equivalent to Northern Portugal and present day Galicia (in Spain), which to this day still bears it's name. They were an independently-minded people who fought against other Iberian tribes, but later eagerly joined forces with some of them to stem the Roman tide.
The lack of horse-related items that exist abundantly in the cultures around them, make us believe that they were almost exclusively foot-soldiers (though they may have, like the Saxons centuries later, ridden to the battlefield and dismounted for combat). Their equipment is very well attested in primary texts, and archaeological finds, notably the famous Callaeci warrior statues.