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A new variational principle for General Relativity, based on an actionfunctional $I\/(\Phi,\nabla)\/$ involving both the metric $\Phi\/$ and theconnection $\nabla\/$ as independent, \emph{unconstrained\/} degrees of freedomis presented. The extremals of $I\/$ are seen to be pairs $\/(\Phi,\nabla)\/$in which $\Phi\/$ is a Ricci flat metric, and $\nabla\/$ is the associatedRiemannian connection. An application to Kaluza's theory of interactinggravitational and electromagnetic fields is discussed.

Variational techniques in general relativity: A metric-affine approach to Kaluza's theory