The Islamic caliphate originally overseen by Muhammad and his successors would eventually fragment.  One of the most dominant successor states was the Abbasid Caliphate.Seen here at its largest extent (around 850 CE), the Abbasids would control vast amounts of land between 750 and 1258 CE.

One point of conflict between the islamic and Christian spheres at this time was with the Byzantine Empire. Although there was conflict, there were also extensive diplomatic contacts. The Abbasids, centered in Baghdad, sponsored an outpouring of art and architecture.

A Description of Baghdad
The work of Ibn Sina, an Arab Physician