From the release:
The "Armorican" peninsula came to be settled with Britons from Britain during the
poorly documented period of the 5th-7th centuries. When Vikings or Northmen settled
in the area in the ninth and early tenth centuries these regions came to be known as
Normandy and the name Armorica fell out of use. Western Armorica eventually evolved
into Brittany, while the east became the Breton March under a Frankish marquis. The
native Armoric Breton were skilled horsemen and their standard weapon was the
javelin, which they continued to use well after neighbouring Nortmans and French
took to charging with the lance.
The new cavalry pack can be used for roughly 600-1100 AD in several armies of the
area as native Breton cavalry was often employed as mercenary.