Why does Islamic flag have a crescent and a star?

It is widely believed that the crescent moon and star is an internationally-recognized symbol of Islam. After all, the symbol is featured on the flags of several Muslim countries and is even part of the official emblem for the International Federation of Red Cross and Red Crescent Societies. read more

While the crescent on its own is depicted as an emblem used on Islamic war flags from the medieval period, at least from the 13th century although it does not seem to have been in frequent use until the 14th or 15th century, the star and crescent in an Islamic context is more rare in the medieval period, but may occasionally be found in depictions of flags from the 14th century onward. read more

The star-and-crescent in the Flag of Pakistan is stated as symbolizing "progress and light" (while the green colour is stated as representing Islam). The star-and-crescent in these flags was not originally intended as religious symbolism, but an association of the symbol with Islam seems to have developed beginning in the 1950s or 1960s. read more