The adjective kaiserlich means "imperial" and was used in the German-speaking countries to refer to those institutions and establishments over which the Kaiser ("emperor") had immediate personal power of control.
In the Early Modern Period the term is linked with the universal precedence of the Kaiser over the other princes of the realm.
Holders of an imperial or kaiserliche office were recruited from the whole empire, and had wide-ranging privileges in the territories.
The kaiserliche soldiers had an especially romanticised calling and loyalty, and occasionally similar names continue to the present day, e.g. in several musical pieces and the Kaiserjäger band.
In Switzerland the term has negative connotations that go back to the protracted struggle for independence of the Swiss Confederation.