  This paper applies methods of Van der Put and Van derPut-Saito to the fourth
Painlev\'e equation. One obtains a Riemann--Hilbert correspondence between
moduli spaces of rank two connections on $\mathbb{P}^1$ and moduli spaces for
the monodromy data. The moduli spaces for these connections are identified with
Okamoto--Painlev\'e varieties and the Painlev\'e property follows. For an
explicit computation of the full group of B\"acklund transformations, rank
three connections on $\mathbb{P}^1$ are introduced, inspired by the symmetric
form for ${\rm PIV}$ as was studied by M. Noumi and Y. Yamada.
