Simplify the following text for a Grade 13 native English-speaking person.
Original: In the 1040s , the Berber Zirids ( governors of North Africa under the Fatimids ) declared their independence from the Fatimids and their recognition of the Sunni Abbasid caliphs of Baghdad , which led the Fatimids to launch devastating BanÅ `` Hilal invasions .
Simplified: In the 1040s , the Zirids ( governors of North Africa under the Fatimids ) declared their independence from the Fatimids and their conversion to Sunni Islam , which led to the devastating BanÅ `` Hilal invasions .