Palazzo Margherita, formerly Palazzo Piombino, is a palazzo on Via Veneto in Rome. The usual name references Queen Margherita of Savoy, who lived there from 1900 to 1926. It now contains a U.S. embassy.
In 1885, the Boncompagni-Ludovisi family chose to sell their ancestral family home in response to a severe financial crisis. The Villa Ludovisi and most of its extensive grounds were sold in 1883 to a property developer, the Società Generale Immobiliare, which in 1885 divided the property into luxury building lots. The family retained a small portion of the original estate around the Casino di Villa Boncompagni Ludovisi, the only building from the original holdings that was not demolished. However, the Casino was not designed to be the primary family home of a noble family.
The Palazzo Piombino was built from 1886 to 1890 by Gaetano Koch for Rodolfo Boncompagni Ludovisi, titular Prince of Piombino, as a new palace for the Boncompagni-Ludovisi family. It occupied one of the new developer lots at a prominent location along the Via Veneto, the new main road that developers had built through the former Villa property.