Overview
from German Kapelle (chapel) and Meister (master), literally "master of the chapel choir" designates the leader of an ensemble of musicians. Originally used to refer to somebody in charge of music in a chapel, the term has evolved considerably in its meaning and is today used for denoting the leader of a musical ensemble, often smaller ones used for TV, radio, and theatres.
Historical usage
In German-speaking countries during the approximate period 1500–1800, the word often designated the director of music for a monarch or nobleman. For English speakers, it is this sense of the term that is most often encountered, since it appears frequently in biographical writing about composers who worked in German-speaking countries. During that period, in Italy, the position (Italian: maestro di capella) largely referred to directors of music assigned to cathedrals and sacred institutions rather than those under royal or aristocratic patronage.
A Kapellmeister position was a senior one and involved supervision of other musicians. Johann Sebastian Bach worked from 1717 to 1723 as Kapellmeister for Prince Leopold of Anhalt-Cöthen. Joseph Haydn worked for many years as Kapellmeister for the Esterházy family, a high-ranking noble family of the Habsburg monarchy. George Frideric Handel served as Kapellmeister for George, Elector of Hanover (who eventually became King George I of Great Britain).
A Kapellmeister might also be the director of music for a church. Thus, Georg Reutter was the Kapellmeister at St. Stephen's Cathedral, Vienna, where his young choristers included both Joseph and Michael Haydn.
From Wikipedia (CC BY-SA 4.0).