When did guru Nanak founder Sikhism?

Guru Nanak was born enlightened. He did not become Guru in is human life but was born a Guru. There are numerous stories about when child Guru Nanak displayed holy and miraculous qualities. For instance, when he was only a child he was sleeping under the sun and a very big snake came and opened its hood over the guru. People thought it was going to attack the guru but they realised it was protecting him from the sun. It did not attack him and when he awoke, it went away. Also, an astrologer predicted that Guru Nanaks parents would have a very holy child. Guru Nanak was born enlightened. He did not become Guru in is human life but was born a Guru. There are numerous stories about when child Guru Nanak displayed holy and miraculous qualities. For instance, when he was only a child he was sleeping under the sun and a very big snake came and opened its hood over the guru. People thought it was going to attack the guru but they realised it was protecting him from the sun. It did not attack him and when he awoke, it went away. Also, an astrologer predicted that Guru Nanaks parents would have a very holy child.