A cikin bazara na 1087, labarai sun isa fadar Byzantine na babbar mamayewa daga arewa. Masu mamayewa Pechenegs ne daga yankin arewa maso yammacin Bahar Maliya; an ba da rahoton cewa sun kai mutane 80,000. Yin amfani da mawuyacin halin da Byzantines ke ciki, ƙungiyar Pecheneg ta nufi babban birnin Byzantine a Constantinople, suna lalata arewacin Balkans yayin da suke tafiya. mamayewar ta haifar da mummunar barazana ga Daular Alexios, duk da haka saboda shekaru na yakin basasa da kuma watsi da sojojin Byzantine ba su iya samar wa sarki isassun sojoji don mamaye Pechenegs ba. An tilasta Alexios ya dogara da ikonsa da ƙwarewar diflomasiyya don ceton daularsa daga hallaka. Ya yi kira ga wata ƙabilar nomadic, Cumbeans, don shiga yaƙi da shi a cikin babban birnin Byzantine: Ina babban birnin Pechenegs?
Ƙasar Constantinople