It is the predominant form of Sunni Islam in the Arabian Peninsula, where most people are Wahabis, subscribing to a far-right interpretation of Salafism. In Egypt, around 5-6 million of the 82 million population are believed to be Salafis. It can also be found in Britain, where Salafism is apparently increasingly popular in universities.
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What is Salafism and should we be worried? | News | The Week UK
Journalist Bruce Livesey estimates Salafi jihadists constitute less than 1 percent of the world's 1.9 billion Muslims (i.e. less than 20 million).