Complex sentence: Estonia's Baltic German minority provided a sizable troop of volunteer militia for the Battalion, which was one of the first fighting units of the Estonian Army, and maintained staunch loyalty to the authority of in the Republic.
Split into simpler sentences: Estonia's Baltic German minority provided a sizable troop of volunteer militia. Thus, the battalion belonged to the first fighting units of the Estonian Army, demonstrated and maintained staunch allegiance and loyalty to authority vested in the Republic.