…Samarra, situated on the left bank of…
836 CE
…Samarra, situated on the left bank of the Tigris River about sixty-eight miles (one hundred and ten kilometers) to the northwest.
Here, al-Mu'tasim builds extensive palace complexes surrounded by garrison settlements for his guards, mostly drawn from Central Asia and Iran (most famously the Turks, as well as the Khurasani Ishtakhaniyya, Faraghina and Ushrusaniyya regiments) or North Africa (like the Maghariba).
Although quite often called Mamluk slave soldiers, their status is quite elevated; some of their commanders bear Sogdian titles of nobility.