When and where did Islam come to be?

Muhammad (Saw) first received the revelation of the Quran from Jibreal (Gabriel) in a the cave of Hira in Mecca. Shortly after, he began to spread the wisdom that Allah (God) gave him and sent down in the Quran.

Islam has been around since the time of Hazrat Adam [as] to the time of now and will continue till the day of judgment.