Hichem Djait: Probably the most important and original scholar on Islam. I have been reading about the origins of the Great Fitnah in Islam. It is easy to discover that the best book there is on the subject is by the brilliant Tunisian scholar, Hichem Djait: La Grande Discorde, which appeared in an excellent Arabic translation but not in an English translation. Djait is largely unknwn in US academia although he is in my opinion one of the best contemporary scholars on Islam. This is a man who is equally fluent in German philosophy--in German--and in French historiography--in French--and in Arabic writings--in Arabic. Only one of his books is available in English, L'Europe et l'Islam. That book should be read along with Said's Orientalism and Rodinson's La Fascination de l'Islam as the essential readings on the subject (and Irwin's latest Dangerous Knowledge, albeit as a critical counterpoint). In the introduction to his book on Fitnah, Djait points out (with surprise) that there are no studies about the subject, with the exception of a book by Taha Husayn which is literary in nature. Husayn (contrary to his reputation) was quite apologetic in his writings on Islam. Djait is great in being critical of Orientalist literature and critical of the early Islamic sources. Politically, Djait surprises me: this brilliant scholar has Saddamist Arab nationalist sympathies.
Hichem Djait's Fitna is incredibly rich, detailed history and the best book on the subject I know of. Whatever you do, don't get the book with the same main title by Kepel. Djait's book is the real thing, and considering the creepy anti-Shiism rising in the Sunni Arab world it's probably worth re-reading.