The churches are often cited as "twin", due to their similar external appearance: they have indeed some differences, in both plan and exterior details.

The origin of the two churches traces back to the 17th-century restoration of what was the main entrance to the Middle Ages and Renaissance Rome, from the Via Flaminia (known as Via Lata and Via del Corso in its urban trait).

Pope Alexander VII commissioned the monumental design of the entrance of Via del Corso to architect Carlo Rainaldi.

This included two churches with central plans, but the different shapes of the two areas available forced deep modifications to the projects.

Santa Maria in Montesanto, erected over a church with the same name that lay at the beginning of Via del Babuino, was occupied by Carmelite friars.

The construction of the present church was begun on July 15, 1662, under the patronage of Cardinal Girolamo Gastaldi, and finished in 1675, with other additions by 1679.

The second chapel is dedicated to Santa Maria Magdalena de Pazzi, designed by Carlo Rainaldi to honor the Carmelite nun canonized by Pope Clemente XI in 1669.

The presbytery is stuccoed with angels by Filippo Carcani and houses the miraculous 15th-century altarpiece of Virgin of Montesanto, which tradition holds was painted by an 11-year-old girl.