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The Abbasids ruled for 200 years before they lost their central control when Wilayas began to fracture in the 10th century ; afterwards , in the 1190 s , there was a revival of their power , which was ended by the Mongols , who conquered Baghdad in 1258 and killed the Caliph Al-Musta ' sim .
 location: Abbasids; location: Baghdad; person: Al-Musta ' sim
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: Abbasids; location: Baghdad; person: Al-Musta ' sim