  We prove that multisoliton solutions of the Korteweg--de Vries equation are
orbitally stable in $H^{-1}(\mathbb{R})$. We introduce a variational
characterization of multisolitons that remains meaningful at such low
regularity and show that all optimizing sequences converge to the manifold of
multisolitons. The proximity required at the initial time is uniform across the
entire manifold of multisolitons; this had not been demonstrated previously,
even in $H^1$.
