In 220 AH (forty years before The Minor Occultation Era), Mu士ta峁m’ ‘Abbasi chose S膩marr膩示 as his new capital
So, he built and made it his center of caliphate.
He bought more than 4000 slaves whom he ordered to wear splendid clothes. [with them, they looked superior than other armies]
They used to ride in Baghdad streets and by markets,
bother the people and sometimes kick them with their horses.
About the main reason of build S膩marr膩示, Ibn Ath墨r (one of the famous historians) wrote:
In 220 AH, Mu士ta峁m went to S膩marr膩示 to build a city there. He did so because he had mentioned,
鈥業 am afraid of armies! If they rebel, they will kill all of slaves. I prefer to be in a location which I can overlook them.鈥
From 230 to 279 AH (for 59 years), The Abbasid Caliphate Center was transferred from Baghdad to Samarra.
But in 279 AH, the caliphate returned to Baghdad.
[Now in 279 AH], Imam Mahd墨 (mgehr) is 24 and it is 19 years after The Minor Occultation鈥
Subsequently, the city of S膩marr膩示 quickly turned into ruins, with only two graves of Imam H膩d墨 and Imam al-Askari (pbu th), and also The Holy Sardab1 still remained there.
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1-聽聽聽聽 It was a cellar in the northwest of the shrine of `Askariin (pbu th), in S膩marr膩示. It was the residence and worship place for Imam H膩d墨 and al-Askari (pbu th) during the hot summer days. According to reports, Imam Mahd墨 (mgehr) was also seen there, in the time of his father’s life. That is the reason for naming the place 鈥淭he Holy Sardab鈥, in The Occultation Era.
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Moravej al-Zahab, Vol. 4, P. 53; Tarikh al-Khulafa, P. 335; Al- K膩mil, Vol. 6, P. 451; Mu’jam al-buldan, Vol. 3, P. 176