- Fall of the Abbasid caliphate was one of the most important changes that were caused by the mongol siege of Baghdad. The Abbasids had been the ruling dynasty of the caliphate since 750, but they were no match for the mongols. The caliphate was officially abolished by Hulagu Khan in 1258.
- The sack of Baghdad was one of the most catastrophic events in Islamic history. The city was destroyed, its libraries were burned, and its people were massacred. The death toll is estimated to have been in the hundreds of thousands.
- The mongol invasion led to the decline of Islamic culture and science. Baghdad had been a major center of learning and culture for centuries, but it was left in ruins after the invasion. Many scholars and scientists were killed or fled the city, and the city's institutions of learning were destroyed.
- The mongol invasion also had a profound impact on the political landscape of the Islamic world. The caliphate was no longer the dominant power in the region, and instead various khanates and emirates were established. This led to a period of political fragmentation and instability in the Islamic world.