In The Name of Allaah, The Most Merciful, The Bestower of Mercy.
In the year 22 AH, the Islamic armies proceeded to the lands of Al-Baab to conquer it. Those lands were inhabited by the Turks, and there the commander of the Islamic army, Abdur Rahmaan Ibn Rabee’ah, met the Turkish king Shahr Baraz. He asked Abdur Rahmaan to make peace and showed willingness to participate in the Islamic army to fight the Armenians.
Abdur Rahmaan sent him the commander Saraqah Ibn Amr, so he received Suraaqah and accepted him. Then he wrote to the Khaleefah Umar Ibn AllKhattaab [may Allaah be pleased with him] informing him of the matter, Umar agreed to what he did and as a result of that, a peace treaty was made and no fighting occurred between the Turks and the Muslims; but rather everyone proceeded to the Armenian lands to conquer them and spread Islam there. The Islamic armies marched to conquer the lands in northeastern Persia until the call to the path of Allaah spread in those lands after the fall of the Persian empire, which was an impregnable barrier in front of the Islamic armies. As a result of the Islamic conquests, the door was open for the people of those countries and regions to move freely, including the Turks. Contact was made with the Muslims, and the Turks embraced Islam and joined the ranks of the Mujahideen to spread Islam and raise the word of Allaah.
During the Khilaafah of Uthmaan Bin Affaan [may Allaah be pleased with him], Tabaristan was conquered, and then the Muslims crossed the Jeihon River in the year 31 AH. They went to the lands beyond the river, and many Turks entered the religion of Islam and became defenders of it and participated in Jihad to spread the call to the path of Allaah. The Islamic armies continued to advance in those regions, so Bukhara was conquered during the Khilaafah of Muaawiyah Bin Abee Sufyan [may Allaah be pleased with him and his father], and these victorious armies penetrated until they reached Samarkand. And as soon as the era of the Islamic state appeared, all the countries beyond the river came under the justice of Islamic rule and these peoples lived under a well established Islamic civilization.
The number of Turks in the court of the caliphs and the Abbasid princes increased and they began to assume leadership and administrative positions in the state, they became soldiers, leaders and writers, and were calm and obedient until they gained the ranks. And when Al-Mu’tasim al-Abbaasee took over the caliphate, he opened the doors to Turkish influence and assigned them to the leadership positions of the state and thus they became involved in state affairs, his policy was aimed at reducing the Persian influence, which had free hand in the administration of the Abbasid state since the era of the Al-Ma’moon’s caliphate. Al-Mu’tasim’s interest in the Turkish caused a state of severe discontent between the people and the soldiers. Al-Mu’tasim feared the people’s vengeance so he established a new city, Samarra, about 125 km from Baghdad, where he lived with his soldiers and supporters. Therfeore, since that date, the Turks began to appear in important roles on the stage of Islamic history, until they established a large Islamic state that had strong ties to the successors of the Abbasid state, known as the Seljuk state. (1)
Jihaad in our times and the guidelines of Jihaad according to Islam
[Ref 1: An Excerpt from Ad-Dawlah Al-Uthmaaniyyah Awaamil An-Nuhood Wa Asbaab As-Suqoot. Vol 6. Pages 23-24.slightly paraphrased]