  We construct Supergravity models where the goldstino multiplet has a
gravitational origin, being dual to the chiral curvature superfield.
Supersymmetry is nonlinearly realized due to a nilpotent constraint, while the
goldstino arises from $\gamma$-traces of the gauge-invariant gravitino field
strength. After duality transformations one recovers, as expected, the standard
Volkov-Akulov Lagrangian coupled to Supergravity, but the gravitational origin
of the goldstino multiplet restricts the available types of matter couplings.
We also construct explicitly some inflationary models of this type, which
contain both the inflaton and the nilpotent superfield.
