He was born in about 280 H. in Salamia. His name was Muhammad, Laqab (Title) al-Qaim bi-Amrillah (Firm in the ordinances of Allah). He had accompanied Imam Mehdi (AS) in his journey to North Africa. He assended the throne of Imamat in 322H.
Expeditions against Egypt:
It may be remembered that Imam al-Qaim had commanded the Fatimi naval
forces in 301 H. The Fatimi fleet sailed from Mahdiya (Town erected by Imam
Mehdi (AS) which is in present day Tunisia) towards the northern coast of
Egypt and returned to Raqada after conquering Tripoli. In the following
year Hubasa bin Yusuf set off east and conquered Surt and Ajabiyya on 7th
Rajab, 301 H. he entered Barqa. On Thursday the 14th Zilhaja, 301 H al-Qaim
followed him from Raqqada with a large army. Contrary to his orders,
Hubasa, without waiting for his arrival, pushed further east and invaded
Alexandria on 2nd Safar, 302 H. Imam al-Qaim arrived there on Friday the
14th Rabiul Akhar, 302 H. The Abbasis succeeded to prevent the Fatimi's
entry in Egypt. At his withdrawal from Egypt, Imam al-Qaim (AS) however
left a garrison in Barqa.
In 307 H, the second attempt had been conducted at the command of al-Qaim (AS). He set out eastward on Monday the 1st Zilqada, 306 H. On Friday the 8th Safar, 307 the vanguard of the army arrived in Alexandria. This time the Fatimi forces made an advance right upto the Egyptian capital before they retreated. These two invasions were launched during the period of Imam Mehdi (AS). Although Egypt did not fall under the Fatemi Empire as a result of these expeditions, the Books that were lost to bandits, during the journey of Imam Mehdi (AS) from Egypt before Zuhur, were recovered. Imam Mehdi (AS) is known to have said "Even if these attempts were made to recover our treasury of knowledge, it was worth it."
Expeditions against Italy (Rome):
On 6 Rajab 322 H, Imam al-Qaim (AS) dispatched a strong squadron of 20
sailing vessels under the command of an Arab Amir al-Bahr (Admiral), Yaqub
bin Ishaq al-Tamimi, who made a successful attack on Italy.
The Fatimi fleet returned in triumph on 26 Ramadan 323 H to Mahdiya. It was due to the domestic rebellion of Abu Yazid Daj'jal (Anti-Christ). The Fatimid fleet, returning to Mahdiya, also occupied islands of Sardinia, Corsica, Malta, Crete and Cyprus for a short while. And here we cannot but call attention to a fact that the Fatimeen were the masters of the entire Mediterranean, and their fleets operated freely throughout its length and breadth.
Rebellion (Fitnat) of Daj'jal (LA):
During his era Imam al-Qaim (AS) had to meet more serious rebellions
hatching in the west. The principle revolt took place amongst the Zanata
(Berber) tribe, south of Kutama territory, who were the Kharijis under the
leadership of Abu Yazid Daj'jal (Anti-Christ). In 332, he marched
northwards and took Baghaya, Tabassa, Marmajana and Laribus. The Fatimi
forces tried to prevent his advance upon Baja, but were repulsed. Abu Yazid
Daj'jal marched towards Kairwan, but this time he suffered defeat. He soon
rallied, and took Raqqada, and then pressed on to Kairwan and captured it.
Mahdiya put up a vigrous resistance for almost a year, repelling Abu Yazid
Daj'jal's repeated attempts to storm the capital.
In 334, Abu Yazid Daj'jal (LA), ordered for massacre and plunder, and captured Tunisia. The Fatimi forces were able to regain the whole Tunisia next year. But, after an interval, Abu Yazid Daj'jal rallied and laid siege to the town of Susa.
We see that Imam al-Qaim was an experienced soldier and an able commander who could lead his forces to victory. He used to participate in military expeditions. He was bold and courageous, and his activities were not confined to his military operations only. He was not harsh towards his opponents and was tolerant. Yet during this rebellion Imam al-Qaim remained calm and at peace, he did not engage himself in war with Abu Yazid Daj'jal (LA) but waited until Mahdiya was under seige. For he had envisioned that this task was to be done under the commands of Imam Mansoor (AS) and by his Barakat only. It is said that when Imam Mehdi (AS) ordered to build Mahdiya, he was heard saying, "This fortress and town are built for the preparation of a single day." That day was when Daj'jal had reached the Musalla (where Eid prayers are held) of Mahdiya. When Abu Yazid Daj'jal reached the gates of Mahdiya, he was informed of the defeat of his army at a certain place and had to turn back. It was then that Imam al-Qaim (AS) broke his silence and revealed that it was a time for all Mumineen to rejoice, for the la'een had reached his limits and will never return.
Imam al-Qaim (AS) passed away on 14th Shawal, 334 H at the height of Abu Yazid Daj'jal's rebellion, who at that time had sieged over Susa. This tragedy was kept a total secret to everyone, including family members, by Imam Mansoor (AS) until Abu Yazid Daj'jal was captured.