This book naturally follows on from Volume I, developing the mathematical foundations and physical applications of the relatively new subject known as Unity Root Matrix Theory (URMT). The mathematical advances extend URMT's new method of arbitrary vector embedding to two arbitrary vectors, in three or more dimensions, by way of a complete reformulation of URMT in terms of projection operators and exterior products. The similarity of the resulting matrix forms to those used in quaternions, rotations and electromagnetism enables URMT to extend its physical applications to angular dynamics and the electromagnetic plane wave. In particular, URMT's inherently discrete nature results in a treatment of quantised particle spin. Armed with a common mathematical formulation of physical applications as an eigenvector solution to a matrix operator, all generated in a language more recognisable to conventional mathematical physics, the path is now clear for closer future development of URMT to existing, and highly successful, physical theories.