During the alternating wars between the Guelphs and Ghibellines, in 1289, the very wealthy banker Geri Spini decided to build the largest private palace in the city of Florence. The palace was the only one that could compete with Palazzo della Signoria: they both had a sensation of volume. The forcefulness of the construction was visible both from Piazza Santa Trinita and also from the Santa Trinita bridge. Unlike the palaces that were built later on, Palazzo Spini still retains the appearance of a
, a medieval example of the great families who had to protect themselves from their fellow citizens. The coating is made of exposed stone and the coping of the battlements is Guelph. The story of the original building is told in Vasari's Vite (Lives), but it can also be admired in Domenico Ghirlandaio's depiction of it in the frescoes in the Sassetti Chapel, in the church of Santa Trinita. In the cycle of frescoes dedicated to the Saint of Assisi, in the scene of the "Resurrection of the boy" Ghirlandaio depicts a miracle that took place in the square, when a child fell from a window of Palazzo Spini and was resuscitated thanks to St Francis's intervention.
A few years after its construction, the building was divided into two properties: one was facing the Arno river and was inhabited by the Spini family until the nineteenth century, while the part facing the square was sold due to financial difficulties in the mid-seventeenth century. The palace was reunified in the nineteenth century thanks to Marquis Feroni.
The Municipal Authority used it during the years when Florence was capital of the Kingdom of Italy and had its offices there until 1881: it was later owned by the Cassa di Risparmio bank. In 1938, it was purchased by Salvatore Ferragamo as the headquarters for his footwear and leather goods design activity that made him famous throughout the world. The Salvatore Ferragamo Museum has been open in the basement since 1995.