Prophet Muhammad (peace be upon him) started receiving God revelation of Quran through the angel Gabriel in year 610 AD (when he was 40 years old).
Islam was started long before prophet Muhammad (PBUH). It was started by God; the Creator; by start of universe creation. However, Islam per God revelation of Quran to prophet Muhammad (PBUH) started by start of Quran revelation through the angel Gabriel to prophet Muhammad (PBUH) on year 632 AD. Refer to questions below.
God revelation of Quran to Prophet Muhammad was through the Angel Gabriel (Jibril) and started in year 610 AD while Prophet Muhammad was in Mecca (Makkah). The Prophet was 40 years ago at start of Quran revelation. Islam is the religion based on Quran holy book. Quran revelation continued until year 632 AD (year of the prophet death).Refer to the related question below for more information on why was Quran revelation.
If you mean Islam per Quran revelation to prophet Muhammad (PBUH), then Islam started by start of first revelation of Quran by God (Allah in Arabic) to prophet Muhammad (PBUH) through the angel Gabriel (Jibril) in year 610 AD. If you mean Islam in its sense of submission to Allah (God in English), the Creator, then Islam started by start of universe creation. refer to related question below.
Prophet Muhammad (peace upon him) started preaching in Makkah (Mecca) in year 610 AD (year of Quran start of revelation by God).
622 A.D., by the founder, Prophet Mohammed._________________________________________________________________Comment on Answer above:Islam in its general meaning started by start of universe creation. However, Islam per Quran God revelation to prophet Muhammad (PBUH) started by start of Quran revelation in year 610 AD. Islam in both cases is fouinded by Allah (God in English). Quran revelation continued through year 623 AD (year of prophet Muhammad (PBUH) death). Refer to question below.
Islam in its universal sense; as full submission to God; is founded by God since start of universe creation. However, Islam per God revelation of Quran to prophet Muhammad through the angel Gabriel started in year 610 AD by start of Quran revelation.
In year 610 AD by start of Quran God revelation to prophet Muhammad (PBUH) through the angel Gabriel (Jibril).
On the first day of Islam religion start per Quran revelation by God to prophet Muhammad through the angel Gabriel. Muslims on the very early days of Islam were used to gather at 'AlArqam home' to learn from prophet Muhammad their Islam teachings.
Islam has been since start of the universe creation. See question below. However, if you mean the Islam religion per God revelation of Quran to prophet Muhammad, then Quran God revelation of Quran started in year 610 AD.
Allah (God in English) is the founder of Islam. Islam in its universal sense was founded by start of universe creation. However, Islam per Quran revelation to prophet Muhammad (PBUH) was started in year 610 AD.
Prophet Muhammad didn't create the Islam religion. He is God prophet to whom God revealed Quran through the angel Gabriel (Jibril) and prophet Muhammad followers were called by God as Muslims and the religion is called by God as Islam, the same religion of all God prophet missions since start of mankind. Refer to question below for more information.
Islam civilization started by start of Quran revelation to prophet Muhammad in year 610 AD. The first verse of Quran is 'Read'. This is the first pillar of any civilization. The real civilization started when people, by Islam, realized the real objectives of their creation.