Once in a place called Mecca, is where Muhammed grew up. It was in the middle of the dessert. It was a bad place full of bad people and false idols.
One day, while he was praying in a cave, the angel Gabrial appeared. She asked Muhammed to recite the words of God. The angel told Muhammed to take his fellow Muslims away from Mecca and go to Medinah.
He was told to go to Medinah, to build the first Mosque.
People tried to kill him, but failed. If they started to chase him, he would hide in a cave.
He said to the people of Medinah, wherever his camel, Casper, stopped, would be where the first mosque would be.
20 years after he died, scripture recorded what Allah had told him.