This book presents a cosmology based on seven Octonion spaces. The spaces are interrelated. One space describes universes such as the QUeST universe previously described by the author. Another space describes Megaverses such as the UTMOST Megaverse of the author. The complete theory appears to be as fundamental as possible. It directly connects to the Unified SuperStandard Theory of the author. Thus it is a complete theory - the first truly comprehensive theory unifying the deepest levels with particle physics experiment.