Answer:
People believe Islam began with Prophet Muhammed, peace be upon him. This is untrue as Islam means - Submission, Peace and Obedience. So, there has been peace and submission during the past so that does mean you are a muslim. All the prophets were Muslims as they submitted themselves to Allah, our(muslims) one and only God. So, Islam started with Prophet Adam, peace be upon him and Eve - may Allah be pleased with her. Islam is submission, to one God. Hope that answers the question and may peace be with you.