Abu Ayyub was one of the Ansar (Arabic: الأنصار, meaning aiders, helpers or patrons) of the early Islamic history, those who supported Muhammad after the hijra (migration) to Medina in 622.

Abu Ayyub was born in Medina, Hejaz as Khalid bin Zayd to the Najjar family of the Banu Khazraj.

The ultimately agreed purchase price was paid by Abu Ayyub al-Ansari who thus became the waqif (or creator of a charitable endowment) of Al-Masjid an-Nabawi on behalf of Muhammad.

[3] Following the Muslim conquest of Egypt, Abu Ayyub moved to Fustat, where he lived in a house adjacent to the mosque of Amr bin Al'aas that had been completed in 642.

"[5] In a hadith in Qital al-Rome, a chapter of Sahih Muslim, Muhammad prophesied that the first army to charge Constantinople will enter Paradise.

Yazid ordered the Muslim army to fulfil his request, and they pushed back the enemy's forces until they reached the walls of Constantinople where Abu Ayyub was finally interred.

About this battle, Aslam ibn 'Imran narrates that when they were fighting the Byzantines, a Muslim soldier penetrated deep into enemy ranks.

[8][unreliable source] “built of white marble by Mehmed II, the Conqueror, in 1459, adjacent to the türbeh of Abu Eyúb Ensari, the legendary standard-bearer of the prophet, whose tomb here was revealed in a vision a few days after the conquest…”[1] After the Conquest of Constantinople by the Ottoman Turks, a tomb was constructed above Abu Ayyub's grave and a mosque built in his honour by Sultan Mehmed the Conqueror.