Military types that existed in Cambridgeshire fell
into three categories:
The Regular Army Regiment was founded in 1689 and eventually became
the 30th Foot (Cambridgeshires) Regiment who were full time, paid,
soldiers. The Volunteer Force was the Cambridgeshire Regiment and
was formed in 1860 from volunteers. The Cambridgeshire Militia was
the oldest force and was formed by conscription, designed as a defensive
force against "foreign enemies and domestic rebels".
of these has it own page here.