The history of Islam
How Islam spread
Within a century of Muhammad's death Arab armies ruled from Spain to the Indus. Conversion followed conquest over centuries, under the jizya tax on non-Muslims; later Islam also spread by trade and Sufi preaching.
The conquests
The Byzantine army was defeated at Yarmuk (636), Jerusalem surrendered (637/638), Egypt fell (641) and the Persian empire collapsed after Nahavand (642). North Africa followed, then Spain (711) and Sindh (711-712). Arab expansion into France was checked at Tours/Poitiers (732).
قَٰتِلُوا۟ ٱلَّذِينَ لَا يُؤْمِنُونَ بِٱللَّهِ وَلَا بِٱلْيَوْمِ ٱلْـَٔاخِرِ وَلَا يُحَرِّمُونَ مَا حَرَّمَ ٱللَّهُ وَرَسُولُهُۥ وَلَا يَدِينُونَ دِينَ ٱلْحَقِّ مِنَ ٱلَّذِينَ أُوتُوا۟ ٱلْكِتَٰبَ حَتَّىٰ يُعْطُوا۟ ٱلْجِزْيَةَ عَن يَدٍ وَهُمْ صَٰغِرُونَ 29
29Fight against such of those who have been given the Scripture as believe not in Allah nor the Last Day, and forbid not that which Allah hath forbidden by His messenger, and follow not the Religion of Truth, until they pay the tribute readily, being brought low.
Quran 9:29 (Pickthall) · context
Under Muslim rule
Jews and Christians were allowed to keep their faith as dhimmis in return for the jizya and legal restrictions. The so-called Pact of Umar lists such restrictions (no new churches, no public crosses); its date and attribution are disputed. Conversion came gradually over centuries. In Southeast Asia Islam spread mainly by trade and preaching from the 13th century.
Today
The Pew Research Center estimated 1.8 billion Muslims in 2015, about 24 percent of the world's population. Indonesia has the largest Muslim population.
Where scholars disagree
- The dating and authenticity of the Pact of Umar are disputed (Mark R. Cohen and others).
Sources
- Earliest source Hugh Kennedy, The Great Arab Conquests (Weidenfeld & Nicolson, 2007).
- Pew Research Center, The Changing Global Religious Landscape (April 2017).
- Mark R. Cohen, Under Crescent and Cross (Princeton, 1994), on the Pact of Umar.