Islam is an Arabic word that means submission to God, the one and only one God. In this sense Islam started with start of universe creation. However Islam per Torah revelation to Moses is called Judaism; Islam per the Bible revelation to Jesus is called Christianity; and Islam per Quran revelation to Muhammad is called the same name Islam. Islam religion per God revelation of Quran to prophet Muhammad (PBUH) started with the revelation of the first verses of Quran to prophet Muhammad through the Angel Gabriel (Jibril) while the prophet was meditating in a mountain cave, called Hiraa, in Mecca (Makkah); that is currently in the Kingdom of Saudi Arabia. This was in year 610 AD.
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Historical Perspective:
When Muhammad (Peace be upon Him) in AD 610 received revelations whilst alone in a cave he knew that he would face many difficulties and opposition but he took the responsibility that was given to him and started preaching the message of Islam.
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Updated Answer
Islam means Submission to God. In this meaning it is the objective of God revelations to all prophets including Noah, Abraham, Isaac, Jacob, Moses, David, Solomon, Jesus until Mohamed. Judaism is the religion according to God revelation to Prophet Moses. Christianity is the religion according to God revelation to Prophet Jesus. The very name Islam is the religion according to God revelation to Prophet Mohamed. Islam , as the religion revelation to Prophet Mohamed, started in year 610 by the revelation of the first verse of Quran (the Islam religion Holy book) in Mecca (in present country Saudi Arabia).
Read more: How_did_Islam_religion_start
it started from the hagar whose son was ismael
Islam.
Islam started in the 6th century, specifically in the year 610 when the Prophet Muhammad received his first revelation in Mecca.
God the Creator started Islam religion by start of universe creation. Refer to question below.
Around 622 ,
Islam started in the seventh century CE.
It started in Mecca in Saudi Arabia
Islam, in its universal sense, started with start of universe creation. Refer to related question below.
Muhammad started teaching Islam religion in the year of 610 A.D
Islam started by start of universe creation. Refer to related question below.
Islam is the only trure religion in the world
Allah (or God in English and same God in Christianity and Judaism) is the origin of Islam religion that means submission to God. It was started by God by start of universe creation. Refer to question below.
Islam started by start of universe creation. Refer to question below for details.