Gülen: "The Face Of Secular Islam"
A man of simple tastes with an austere lifestyle, he portrays himself as the spiritual leader of secular Islamists.
The message he preaches is one of tolerance, promoting a private, non-politicised form of Islam, which can peacefully coexist with Turkey's strongly secular state.
He was born in 1938 in eastern Turkey. He graduated in divinity and obtained a license to preach and teach.
He has written many books and articles and is regarded as a scholar.
Fine academic records
But he is perhaps best known for his role in setting up hundreds of schools across Turkey, Central Asia, the Middle East and Europe run by an Islamic brotherhood known as the "Fethullahcilar", or disciples of Fethullah.
The Turkish military maintains that these schools, financed through charitable trusts, are being used to "brainwash" young people.
But Mr Gülen's supporters insist that they are not religious in outlook.
They point to the broad range of subjects taught there and the schools' fine academic records.
Acceptable face of Islam
Their pupils often fare well in university placement tests, while the schools themselves have frequently won competitions or awards.
Over the years, many of Mr Gülen's followers and pupils have become influential and wealthy.
Until recently, the Turkish establishment appeared delighted by the way in which these institutions have enhanced Turkey's international image.
The schools, which promote Turkey and Turkish culture, have certainly helped boost Ankara's cause in the former Soviet Union over the past decade, as it competed for influence with other regional powers in the new Central Asian republics.
'Plotting against the state'
Until now, Turkish politicians have largely accepted Mr Gülen as the moderate and acceptable face of Islam.
Many have been happy to be linked to a man who is alleged to have hundreds of thousands of followers worldwide - and even to be photographed with him in the hope of improving their own electoral chances.
Mr Gülen's work has also attracted international recognition, and in 1998 he was received by the Pope.
But the powerful Turkish military, which regards itself as the guardian of Turkey's secular tradition, has always remained suspicious of Mr Gülen's motives.
He has now been charged with plotting to overthrow the country's secular state, and allegation that Mr Gülen - and his followers - are likely to vehemently deny.
BBC
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