For a generalisation of the classical theory of Hopf algebra over fields, A.
Brugui\`eres and A. Virelizier study opmonoidal monads on monoidal categories
(which they called {\em bimonads}). In a recent joint paper with S. Lack the
same authors define the notion of a {\em pre-Hopf monad} by requiring only a
special form of the fusion operator to be invertible. In previous papers it was
observed by the present authors that bimonads yield a special case %Hopf monads
may be considered as a special case of an entwining of a pair of functors (on
arbitrary categories). The purpose of this note is to show that in this setting
the pre-Hopf monads are a special case of Galois entwinings. As a byproduct
some new properties are detected which make a (general) bimonad on a Cauchy
complete category to a Hopf monad. In the final section applications to
cartesian monoidal categories are considered.