The 20th Imam, Imam Mansoor Al-Aamir Bi-ahkaamillah SA was born on the 13th of Moharram-ul-Haraam 490H in Al-Qahera (Cairo).
He ascended the throne of Imamate at the age of five following the passing away of Imam Musta`li Billah AS. The oath of allegiance for the Imam was conducted that very day in the court and letters were sent to distant territories notifying them of the 19th Imam`s passing away and the succession of the 20th Imam.
During his reign the Romans captured Damascus. The Imam SA sent Al-Afzal with an army towards the transgressors and forced them into retreat. This was a major victory for the Imam SA and Al-Afzal returned bringing with him the spoils of war.
In another uprising led by a man called ?Sumbus? Al-Qahera was besieged for a number of days. An Armenian guard involved in the siege relates that, “One night I and my men saw the gates of Al-Qahera open and a lone horseman emerge. We hid ourselves so that we could monitor his intentions and lo it was the Imam himself! We followed furtively to see where he was heading. We then saw him SA meet another horseman. They greeted each other and dismounted from their steeds. At that moment we thought of ambush but were awestruck by the Imam`s SA presence and could only look on.
The other horseman humbly enquired as to the Imam`s route and he answered, “I have set forth to assist my army in vanquishing Sumbus and his followers.”
The Imam`s SA army assembled and there was a heated battle. Amidst this the Imam SA and the horseman laid out two kerchiefs on the ground and prayed two rak`at namaaz. The horseman then beseeched the Imam SA to return to the safety of Al-Qahera pleading with him, “O Waliyullah! We will suffice for you in this encounter.” They then parted company and the Imam SA returned through the gates to Al-Qahera and in the morning news was received that Sumbus had been slain.” The Armenian soldier and his companions who witnessed the Imam`s glory entered into the fold and gave their oath of allegiance.
The Imam?s SA Dawat was widespread. In Yemen under the auspices of Molatena Hurratul-Maleka RA and Syedna Yahya RA the Dawat`s foundations became well established. In the year 513H the Imam SA sent Ali-bin-Ibrahim, also known as Najeeb-u-Daulat, to Yemen and the affairs of the army there were entrusted to him by Molatena Hurratul-Maleka RA.
In 515H the Imam`s SA wazir Al-Afzal passed away and he appointed Abul Mansoor Al-Mamoon in his place. In 520H Syedna Yahya-bin-Lamak RA passed away in The Yemen.
In the year 524H, on the 4th of Rabi-ul-Akhar, the 21st Imam, Molana-al-Imam Al-Taiyyeb AS was born.
A historian of those times, Ibn-Muyesser who was also a judge, records in the chronicles of Misr (Egypt):
“The Imam SA informed all of the glad tidings of the birth of his son Imam Taiyyeb AS and that he was indeed his successor. All of Misr was decorated to mark this occasion especially the palaces, which were embellished with grand banners and utensils of gold and silver.
On the 14th day the kabash for aqiqah was dressed up in silk finery and silver ornaments before zabihat. The newborn Imam SA was brought into court and I was one of those who had the honour of holding the 21th Imam SA.
Throughout that entire day gold coins were distributed amongst the public. Exotic fruits from far-off orchards were distributed in the palaces and the scent of musk and amber emanated from all around.”
The Imam AS sent Sharif Mohammed-bin-Haidara to The Yemen with the Sijil-ul-Bisharat for Maulatena Hurratul-Maleka RA informing her of the birth of the 21st Imam SA and the nas on him.
The Imam SA also sent an old handkerchief which Sharif was instructed to give her. He put it amongst his clothes and forgot about it. When questioned by her as to if the Imam SA had sent anything else with him he initially said no.
Then one day during his stay, as he was sorting through his clothes he saw the old handkerchief. He immediately rushed to Molatena Hurratul-Maleka RA. As he handed it over he begged her forgiveness for his negligence. At the sight of the old handkerchief she began to weep. Imam had foretold her of his death.
The Imam SA used to often allude to this eventuality to his close followers. One day a platter of citrons was presented to the Imam SA in court. He chose a big citron and stabbed it with numerous knives announcing to those seated ? Soon I will be amidst you pierced like this citron!? At times he would say I am a miskeen, the son of a miskeen! To be slain by the sikkeen (blade)!?
In 526H on the 3rd Zilqadah, the Imam SA was touring the city in a grand procession with cavalry, regalia, flags and guardsmen. The Nizari people had been plotting to slay the Imam SA and had one of their number commit suicide by jumping off a high minaret. Chaos ensued and most of the procession left their guard to see what had happened. The Nizaris grabbed this opportunity, surrounded the Imam SA and attacked him with poisoned knives. The Imam SA collapsed to the ground.
He was taken to the palace, where he assembled all the Huduud and Abwaab and restated the nas on Molana Al-Imam A-Taiyyeb SA.
The administration of the kingdom was entrusted to the Imam`s SA uncle`s son Abdul-Majeed and an oath was taken from him that he would hand over power to the 21st Imam SA.
The Imam had informed his Baab-ul-Abwaab, Ibn-Madyan, of his impending assassination and instructed him to appoint his son-in-law Abu-Ali to his position and to join Imam Taiyyeb SA in seclusion.
On the 4th of Zilqadah, in Al-Qahera, Imam Aamir SA passed away to his heavenly abode. His reign on the throne of the Imamate had lasted 32 years. Allah`s salawaat and salaam upon Imam Aamir Bi-Ahkaamillah SA.