Muhammad I Abul-Abbas was the fifth emir of the Aghlabid

Aghlabid

The Aghlabids were a dynasty of emirs, members of the Arab tribe of Bani Tamim, who ruled Ifriqiya, nominally on behalf of the Abbasid Caliph, for about a century, until overthrown by the new power of the Fatimid.-History:...

s in Ifriqiya

Ifriqiya

In medieval history, Ifriqiya or Ifriqiyah was the area comprising the coastal regions of what are today western Libya, Tunisia, and eastern Algeria. This area included what had been the Roman province of Africa, whose name it inherited....

 (ruled 841–856).

Muhammad I was the son of the fourth emir, Abu Iqal (838–841). Under him the Aghlabids continued their expansion into the Mediterranean, conquering Taranto

Taranto

Taranto is a coastal city in Apulia, Southern Italy. It is the capital of the Province of Taranto and is an important commercial port as well as the main Italian naval base....

 and Bari

Bari

Bari is the capital city of the province of Bari and of the Apulia region, on the Adriatic Sea, in Italy. It is the second most important economic centre of mainland Southern Italy after Naples, and is well known as a port and university city, as well as the city of Saint Nicholas...

 (841) in Apulia

Apulia

Apulia is a region in Southern Italy bordering the Adriatic Sea in the east, the Ionian Sea to the southeast, and the Strait of Òtranto and Gulf of Taranto in the south. Its most southern portion, known as Salento peninsula, forms a high heel on the "boot" of Italy. The region comprises , and...

 and Messina in Sicily

Sicily

Sicily is a region of Italy, and is the largest island in the Mediterranean Sea. Along with the surrounding minor islands, it constitutes an autonomous region of Italy, the Regione Autonoma Siciliana Sicily has a rich and unique culture, especially with regard to the arts, music, literature,...

 (843). In 846 an Aghlabid force seized Rome

Rome

Rome is the capital of Italy and the country's largest and most populated city and comune, with over 2.7 million residents in . The city is located in the central-western portion of the Italian Peninsula, on the Tiber River within the Lazio region of Italy.Rome's history spans two and a half...

 and plundered the Vatican

Vatican Hill

Vatican Hill is the name given, long before the founding of Christianity, to one of the hills on the side of the Tiber opposite the traditional seven hills of Rome...

, though they were not able to hold onto Rome and Taranto

Taranto

Taranto is a coastal city in Apulia, Southern Italy. It is the capital of the Province of Taranto and is an important commercial port as well as the main Italian naval base....

 and Bari

Bari

Bari is the capital city of the province of Bari and of the Apulia region, on the Adriatic Sea, in Italy. It is the second most important economic centre of mainland Southern Italy after Naples, and is well known as a port and university city, as well as the city of Saint Nicholas...

 soon detached themselves from the Aghlabids and submitted to the Abbasid

Abbasid

The Abbasid Caliphate or, more simply, the Abbasids , was the third of the Islamic caliphates. It was ruled by the Abbasid dynasty of caliphs, who built their capital in Baghdad after overthrowing the Umayyad caliphate from all but the al-Andalus region....

s in Baghdad

Baghdad

Baghdad is the capital of Iraq, as well as the coterminous Baghdad Governorate. The population of Baghdad in 2011 is approximately 7,216,040...

.

In Ifriqiya

Ifriqiya

In medieval history, Ifriqiya or Ifriqiyah was the area comprising the coastal regions of what are today western Libya, Tunisia, and eastern Algeria. This area included what had been the Roman province of Africa, whose name it inherited....

 agriculture and trade flourished and there was new urban construction, notably of the great mosques of Sousse

Sousse

Sousse is a city in Tunisia. Located 140 km south of the capital Tunis, the city has 173,047 inhabitants . Sousse is in the central-east of the country, on the Gulf of Hammamet, which is a part of the Mediterranean Sea. The name may be of Berber origin: similar names are found in Libya and in...

 und Sfax

Sfax

Sfax is a city in Tunisia, located southeast of Tunis. The city, founded in AD 849 on the ruins of Taparura and Thaenae, is the capital of the Sfax Governorate , and a Mediterranean port. Sfax has population of 340,000...

. Muhammad's reign was briefly interrupted by the usurpation of his brother Abu Ja'far Ahmad, who like his Abbasid contemporary Al-Wathiq

Al-Wathiq

Al-Wathiq ibn Mutasim was an Abbasid caliph who reigned from 842 until 847 AD .-Biography:...

 supported the Mu'tazili

Mu'tazili

' is an Islamic school of speculative theology that flourished in the cities of Basra and Baghdad, both in present-day Iraq, during the 8th–10th centuries. The adherents of the Mu'tazili school are best known for their having asserted that, because of the perfect unity and eternal nature of God,...

 and persecuted their Sunni opponents, executing some and imprisoning others, like the Maliki

Maliki

The ' madhhab is one of the schools of Fiqh or religious law within Sunni Islam. It is the second-largest of the four schools, followed by approximately 25% of Muslims, mostly in North Africa, West Africa, the United Arab Emirates, Kuwait, and in some parts of Saudi Arabia...

 jurist Sahnun

Sahnun

Sahnun ibn Sa'id ibn Habib at-Tanukhi was a jurist in the Maliki school from Qayrawan in modern-day Tunisia.-Biography:...

; when Muhammad I regained the throne in 847, he sent his brother into exile and rehabilitated the Sunnis, making Sahnun chief qadi

Qadi

Qadi is a judge ruling in accordance with Islamic religious law appointed by the ruler of a Muslim country. Because Islam makes no distinction between religious and secular domains, qadis traditionally have jurisdiction over all legal matters involving Muslims...

 of Ifriqiya.

Muhammad I was succeeded by Ahmad ibn Muhammad (856–863).