  The main goal of this paper is to introduce the notion of a primitive form
for a generic family of Hurwitz covers of $\mathbb{P}^1$ with a fixed
ramification profile over infinity. We prove that primitive forms are in
one-to-one correspondence with semi-simple Frobenius structures on the base of
the family. Furthermore, we introduce the notion of a polynomial primitive form
and show that the corresponding class of Frobenius manifolds contains the
Hurwitz Frobenius manifolds of Dubrovin. Finally, we apply our theory to
investigate the relation between the Eynard--Orantin recursion and Frobenius
manifolds.
