"High" . "took Baghdad" . "year-long siege" . . . "besieged" . . . "Siege of Baghdad (812\u2013813)" . . "long siege" . . "0813-09-28" . "laid siege" . "siege of the city" . "defeating and killing" . . "Decisive victory ofAl-Ma'mun's forces" . . . . . "Siege of Baghdad (865)" . . "siege of Baghdad (812\u2013813)" . "Siege of Baghdad" . "Al-Ma'mun's forces" . "The siege" . "two-year siege" . . . "brutal year-long siege" . . "captured" . . "Al-Amin's forces" . . "Siege of Baghdad (812\u2013813)" . . "siege of Baghdad" . .