Muslim Arabs defeated the Sassanids and
Byzantines as they marched into the Caucasus region. The Arabs made Caucasian Albania a vassal state after the Christian resistance, led by Prince Javanshir, surrendered in 667. Kura and Aras rivers as Arran. During this time, Arabs from Basra and Kufa came to Azerbaijan and seized lands that the indigenous peoples had abandoned.
Seljuq period of Azerbaijan's history was possibly even more pivotal than the Arab conquest as it helped shape the ethno-linguistic nationality of the modern Azerbaijani Turks.
After the decline of the
Abbasid Caliphate, the territory of Azerbaijan was under the sway of numerous dynasties such as the Salarids,Sajids, Shaddadids, Rawadids and Buyids. However at the beginning of the 11th century, the territory was gradually seized by waves ofOghuz Turkic tribes emanating from Central Asia. The first of these Turkic dynasties was the Ghaznavids from northern Afghanistan, who took over part of Azerbaijan by 1030. They were followed by the Seljuqs, a western branch of the Oghuz who conquered all of Iran and the Caucasus and pressed on to Iraq where they overthrew the Buyids in Baghdad in 1055.
The Seljuqs became the main rulers of a vast empire that included all of Iran, Iraq, and Azerbaijan until the end of 12th century. During the Seljuq period, the influential vizier of the Seljuq sultans,
Nizam ul-Mulk (a noted Persian scholar and administrator) is noted for having helped introduce numerous educational and bureaucratic reforms. His death in 1092 marked the beginning of the decline of the once well-organized Seljuq state that further deteriorated following the death of Sultan Ahmad Sanjar in 1153
The Age of the Caliphs.