The Ridda wars also known as the Wars of Apostasy, were a series of military campaigns against the rebellion of several Arabian tribes launched by the Caliph

Caliph

The Caliph is the head of state in a Caliphate, and the title for the ruler of the Islamic Ummah, an Islamic community ruled by the Shari'ah. It is a transcribed version of the Arabic word   which means "successor" or "representative"...

 Abu Bakr

Abu Bakr

Abu Bakr was a senior companion and the father-in-law of the Islamic prophet Muhammad. He ruled over the Rashidun Caliphate from 632-634 CE when he became the first Muslim Caliph following Muhammad's death...

 during 632

632

Year 632 was a leap year starting on Wednesday of the Julian calendar. The denomination 632 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.- Asia :* January 27 – Annular eclipse of the...

 and 633

633

Year 633 was a common year starting on Friday of the Julian calendar. The denomination 633 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.- Europe :* Oswald of Bernicia becomes Bretwalda.* Osric...

 AD, after prophet Muhammad

Muhammad

Muhammad |ligature]] at U+FDF4 ;Arabic pronunciation varies regionally; the first vowel ranges from ~~; the second and the last vowel: ~~~. There are dialects which have no stress. In Egypt, it is pronounced not in religious contexts...

 died.
The revolts, in Islamic historiography later interpreted as religious, were in reality mainly political. However, these revolts also had a religious aspect: Medina

Medina

Medina , or ; also transliterated as Madinah, or madinat al-nabi "the city of the prophet") is a city in the Hejaz region of western Saudi Arabia, and serves as the capital of the Al Madinah Province. It is the second holiest city in Islam, and the burial place of the Islamic Prophet Muhammad, and...

 had become the centre of a social and political system, of which religion was an integral part; consequently it was inevitable that any reaction against this system would have a religious aspect.
In about the middle of May 632, Muhammad

Muhammad

Muhammad |ligature]] at U+FDF4 ;Arabic pronunciation varies regionally; the first vowel ranges from ~~; the second and the last vowel: ~~~. There are dialects which have no stress. In Egypt, it is pronounced not in religious contexts...

, now ailing, ordered a large expedition to be prepared against the Roman empire in order to ward against Roman conquest.