The 100: A Ranking of the Most Influential Persons in History, New York: Hart Publishing Company, Inc. 1978, p. 33:
My choice of Muhammad to lead the list of the world's most influential persons may surprise some readers and may be questioned by others, but he was the only man in history who was supremely successful on both the religious and secular levels. Of humble origins, Muhammad founded and promulgated one of the world's great religions, and became an immensely effective political leader. Today, thirteen centuries after his death, his influence is still powerful and pervasive. The majority of the persons in this book had the advantage of being born and raised in centers of civilization, highly cultured or politically pivotal nations. Muhammad, however, was born in the year 570, in the city of Mecca, in southern Arabia, at that time a backward area of the world, far from the centers of trade, art, and learning.

First, Muhammad played a far more important role in the Development
of Islam than Jesus did in the development of Christianity. Although Jesus was
responsible for the main ethical and moral precepts of Christianity (insofar as
these differed from Judaism), st. Paul was the main developer of Christian
theology, its principal Proselytizer and the author of a large portion of the New
Testament.
Muhammad, however, was responsible for both the theology
of Islam and its main ethical and moral principles. In addition, he played the
key role in proselytizing the new faith, and in establishing the religious
practices of Islam. Michael h. Hart in his book - “the 100”-pages 38/39
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