Read the timeline below. To which religious group do these events refer?

633-637, they took control
of Byzantine Syria and
Palestine and seized most
of Mesopotamia from the
Sassanids
651, they controlled
the Sassanid Dynasty
and Persia.
640s, they conquered
Byzantine Egypt and North
Africa
They allowed
conquered people to
maintain their own
religious practices but
had to pay a tax if they
did not convert to this
religion.
718, they controlled Hindu
India, northwestern Africa,
and the Iberian Peninsula

These events refer to the Islamic religion and the expansion of the Islamic Caliphate.