g the archangel Gabriel in a vision, he proclaimed
himself as a prophet of God. After preaching his doctrine for three
years, and gaining a few converts (the first of whom was his wife,
Khadija), the people of Mecca rose against him and he was forced to
flee from the city in 614. New visions and subsequent conversions of
influential Arabs strengthened his cause, especially in Medina, whither
Muhammed was forced to flee a second time from Mecca in 622, this second
flight being known as the Hegira, from which dates the Muhammedan era.
In the next year, at Medina, he built his first mosque and married
Ayesha, and in 624 was compelled to defend his pretensions by an appeal
to arms. He was at first successful, and thereupon appointed Friday as
a day of public worship, and, being embittered against the Jews, ordered
that the attitude of prayer should no longer be towards Jerusalem, but
towards his birthplace, Mecca. In 625 the Muhammedans were defeated by
the Meccans, but one tribe after another submitted to him, and after a
series of victories Muhammed prepared, in 629, for further conquests
in Syria, but he died in 632 before they could be accomplished. His
successors were known as caliphs, but from the very first his disciples
quarrelled about the leadership, some affirming the rights of Ali,
who had married Muhammed's daughter, Fatima, and others supporting
the claims of Abu Bekr, his father-in-law. There was also a religious
quarrel concerning certain oral traditions relating to the Koran, or
the Muhammedan sacred scriptures. Those who accepted the tradition were
known as Sunnites, and those who rejected it as Shiites, the latter
being the supporters of Ali, both sects, however, being known as Moslems
or Islamites. Omar, a Sunnite, obtained the leadership in 634, and
proceeded to carry out the prophet's ambitious schemes of conquest.
He subdued successively Syria, Palestine, and Phoenicia, and in 639
directed operations against Egypt. The general in charge of this
expedition was Amr, who led four thousand men against Pelusium, which
surrendered after a siege of thirty days. This easy victory was crowned
by the capture of Alexandria. Amr entered the city on December 22, 640,
and he seems to have been surprised at his own success. He immediately
wrote to the caliph a letter in which he says:

"I have conquered the town of the West, and I cannot recount all it
contains within its walls. It contains four thousand baths and tw