This is a sequel to our paper on nonlinear completely positive maps and dilation theory for real involutive algebras, where we have reduced all representation classification problems to the passage from a C * -algebra A to its symmetric powers S n (A), resp., to holomorphic representations of the multiplicative * -semigroup (A, ·). Here we study the correspondence between representations of A and of S n (A) in detail. As S n (A) is the fixed point algebra for the natural action of the symmetric group Sn on A ⊗n , this is done by relating representations of S n (A) to those of the crossed product A ⊗n ⋊ Sn in which it is a hereditary subalgebra. For C * -algebras of type I, we obtain a rather complete description of the equivalence classes of the irreducible representations of S n (A) and we relate this to the Schur-Weyl theory for C * -algebras. Finally we show that if A ⊆ B(H) is a factor of type II or III, then its corresponding multiplicative representation on H ⊗n is a factor representation of the same type, unlike the classical case A = B(H). Mathematics Subject Classification 2010: 46L06, 22E66, 46L45