Ivan Asen II of Bulgaria
Overview
 
Ivan Asen II—also known as a coup, putsch, and overthrow—is the sudden, extrajudicial deposition of a government, usually by a small group of the existing state establishment—typically the military—to replace the deposed government with another body; either...

 in Serbia toppled Stefan Radoslav, a son-in-law of Theodore of Epirus, and replaced him with his brother Stefan Vladislav I, a son-in-law of Ivan Asen II.
 
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