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Background Consolidation of East Syrian Christianity in northern Mesopotamia By the end of the thirteenth century , although isolated East Syrian outposts persisted to the southeast of the Great Zab , the districts of northern Mesopotamia included in the metropolitan provinces of Mosul and Nisibis were clearly regarded as the heartland of the Church of the East .
 location: Mosul; location: Nisibis
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 location: Mosul; location: Nisibis