noun
militia
muh-LISH-uh/məˈlɪʃə/
An armed group of civilians organized for military purposes.
The militia gathers civilian volunteers with safely lowered rifles.

Etymology
The Latin noun named military service rather than a particular army. English later used it for a citizen force, whose members could be called into service for emergencies rather than serving as regular soldiers.
In context
Defending the island was some 700 knights and a few thousand mercenaries and local militia. The odds were not just long, they were impossible.