Then he ordered al-Hashimiya (city) to be built...

Then he ordered al-Hashimiya (city) to be built, that it might be the capital of his government. The Battle of al-Zaab When Abu al-'Abbas al-Saffah undertook the office of the caliphate, he sent his military forces headed by Muhammed b. 'Abd Allah b. 'Ali to fight against the Umayyad king, Merwan al-Himar (the Donkey). 'Abd Allah along with his great army walked and covered the desert; they met the army of the enemy at al-Zaab, near al-Mousil.

The standards of the 'Abbasids were carried by some men riding camels called al-Bukht. He used the wood of willow and other trees along with them in stead of spears. When Merwan saw them, he became terrified and asked those who were around him: "Do you not see that their spears are as thick as date-palms?

Do you not see that their standards on those camels are as black as black clouds?" While he was looking at them with a heart full of terror and fear, large groups of ravens flew and alighted in front of the army of 'Abd Allah, so their blackness connected with that of those black standards, and they became like the black night, [1] Ibn al-Athir, Tarikh, vol. 4, p. 325.

so Merwan became very afraid and asked: "Do you not see that the blackness has connected the blackness, to the extent that they all have become like black, thick clouds?" Then Merwan turned to a man beside him and asked him with terror and fear: -Do you not know the commander of their army? -'Abd Allah b. 'Ali b. al-'Abbas b. 'Abd al-Muttalib. -Woe unto you! Is he one of al-'Abbas's sons? -Yes. -By Allah, I wish that 'Ali b. Abi Talib was in his place in that rank!

Merwan was sure of his inevitable fate; he wished that the conqueror would be Imam 'Ali, the Commander of the faithful, that he might meet them with pardon, kindness, and forgiveness. Any way, the man did not understand Merwan's statement and thought that he accused Imam 'Ali of cowardice, so he opposed him, asking: -Why do you say that concerning 'Ali though he is brave? -Woe unto you! Although 'Ali was brave, he was religious! The religion is other than kingdom!

We narrate on the authority of our old people that 'Ali and his sons had nothing to do with kingdom![1] The fire of the war broke out between the two parties. Immediately the armies of the Umayyads were fully defeated. Merwan and some groups of his army escaped. They reached Mousil, but its inhabitants prevented them from entering it out of fear of the vengeance of the 'Abbasid, victorious army.