His wives included the widow of his uncle Tughril, a Kara-Khanid princess known as Aka or Seferiye Khatun, and the daughter or niece of Bagrat IV of Georgia (who would later marry his vizier, Nizam al-Mulk).

[7] Alp Arslan accompanied his uncle Tughril on campaigns in the south against the Fatimids while his father Chaghri remained in Khorasan.

While there, his father introduced him to Nizam al-Mulk, one of the most eminent statesmen in early Muslim history and Alp Arslan's future vizier.

Arslan defeated Kutalmish for the throne and succeeded on 27 April 1064 as sultan of the Seljuk Empire, thus becoming the sole monarch of Persia from the river Oxus to the Tigris.

With peace and security established in his dominions, Arslan convoked an assembly of the states, and in 1066, he declared his son Malik Shah I his heir and successor.

[13] With the hope of capturing Caesarea Mazaca, the capital of Cappadocia, he placed himself at the head of the Turkoman[14] cavalry, crossed the Euphrates, and entered and invaded the city.

Alp Arslan handed control of his army to his eunuch slave general, Taranges, and commanded him to "Win or be beheaded.

After agreeing on a ransom, Alp Arslan sent Romanos to Constantinople with a Turkish escort, carrying a banner above the disgraced emperor that read: "There is no god but Allah and Muhammad is his messenger".

The Fatimids were launching devastating raids on the Seljuk domains during this period, Arslan may have worried that executing the Roman emperor might escalate his conflict with the Byzantines.

"[25] Alp Arslan and his successor Malik Shah urged Turkish tribes to invade and settle Anatolia where they would not only cease to be a problem for the Seljuk Sultanate but also extend its territory further.

Alp Arslan commanded the Turks as follows: Henceforth all of you be like lion cubs and eagle young, racing through the countryside day and night, slaying the Christians and not sparing any mercy on the Roman nation.

[26][27]Alp Arslan's victories changed the balance in western Asia completely in favor of the Seljuq Turks and Sunni Muslims.

Domestic affairs were handled by his able vizier, Nizam al-Mulk, the founder of the administrative organization that characterized and strengthened the sultanate during the reigns of Alp Arslan and his son, Malik Shah.

He not only had enough food from his subjects to maintain his military, but the taxes collected from traders and merchants added to his coffers sufficiently to fund his continuous wars.

Suleiman ibn Qutalmish was the son of the contender for Arslan's throne; he was appointed governor of the north-western provinces and assigned to complete the invasion of Anatolia.

And they say his arrow never went astray.... From the top button of his hat to the end of his moustaches it was two yards"[29] Muslim sources show Alp Arslan as fanatically pious but just.

[30] His vizier, Nizam al-Mulk, described the young sultan:[31] He was exceedingly imperious and awe-inspiring and, because he was so earnest and fanatical in his beliefs and disapproved of the Shafi‘i rite, I lived in constant fear of him.After Manzikert, the dominion of Alp Arslan extended over much of western Asia.

Perhaps over-eager to press on against his Qarakhanid enemy, Alp Arslan gained the governor's submission by promising the rebel 'perpetual ownership of his lands'.

When he was produced a captive in the royal tent, the sultan, instead of praising his valor, severely reproached his obstinate folly: and the insolent replies of the rebel provoked a sentence, that he should be fastened to four stakes, and left to expire in that painful situation.

At this command, the desperate Yusuf al-Kharezmi, drawing a dagger, rushed headlong towards the throne: the guards raised their battle-axes; their zeal was checked by Alp Arslan, the most skilful archer of the age: he drew his bow, but his foot slipped, the arrow glanced aside, and he received in his breast the dagger of Yusuf al-Kharezmi, who was instantly cut in pieces.

"In my youth," said Alp Arslan, "I was advised by a sage to humble before God; to distrust my own strength; and never to despise the most contemptible foe.

Yesterday, as from an eminence I beheld the numbers, the discipline, and the spirit, of my armies, the earth seemed to tremble under my feet; and I said in my heart, Surely thou art the king of the world, the greatest and most invincible of warriors.

Four days later on 24 November 1072, Alp Arslan died and was buried at Merv, having designated his 18-year-old son Malik Shah as his successor.