Samarra: the new capital established by caliph al-Mu`tasim in 836 to house his growing and much-dreaded personal army of Turkish slave-warriors (mamluks) on the Tigris, 60 miles north of Baghdad. It developed into a conglomeration of secluded caliphal palaces and houses for the troops on a grandiose scale and remained capital until 883 when it was abandoned and Baghdad regained its old position.