Grossone - Ercole I

Ercole I d'Este came to power in 1471 after outmaneuvering his nephew Niccolò in a succession dispute that briefly threatened to destabilize Ferrara entirely. His monetary program reflected broader ambitions — Ferrara's grossone was part of a conscious effort to position the duchy as a credible economic actor among the larger northern Italian states, issuing a substantial silver denomination at a moment when the Este court was also financing Borso's Bible and building the Addizione Erculea, the rational urban expansion that nearly doubled the city's footprint.

MIR 257 is not a rare type, but survivors in honest circulated condition are less common than the reference numbers suggest.