Ex·ar'chate noun [ Late Latin exarchatus , from Latin exarchus : confer French exarchat .] The office or the province of an exarch. Jer. Taylor. Found on http://www.encyclo.co.uk/webster/E/80
Exarchate is a name of a province or territory under an exarch, or viceroy. In the 6th century Justinian formed the middle part of Italy into a province of the Eastern Empire, and gave the government of it to an exarch. Found on http://www.probertencyclopaedia.com/browse/AE.HTM