  We develop the theory of integrable representations for an arbitrary maximal
parabolic subalgebra of an affine Lie algebra. We see that such subalgebras can
be thought of as arising in a natural way from a Borel--de Siebenthal pair of
semisimple Lie algebras. We see that although there are similarities with the
represenation thery of the standard maximal parabolic subalgebra there are also
very interesting and non--trivial differences; including the fact that there
are examples of non--trivial global Weyl modules which are irreducible and
finite--dimensional. We also give a presentation of the endomorphism ring of
the global Weyl module; although these are no longer polynomial algebras we see
that for certain parabolics these algebras are Stanley--Reisner rings which are
both Koszul and Cohen--Macaualey.
