Variational formulation of general relativity from 1915 to 1925 'Palatini's method' discovered by Einstein in 1925

Among the three basic variational approaches to general relativity, the metric-affine variational principle, according to which the metric and the affine connection are varied independently, is commonly known as the ''Palatini method''. In this paper the history of the ''golden age'' of general relativity is revisited through a discussion of the papers involving a variational formulation of the field problem. In particular it is found that the original Palatini paper of 1919 was rather far from what is usually meant by ''Palatini's method'', which was instead formulated, by Einstein in 1925. (author)