Monument of Pope Leo XI

Algardi had no major commissions for monumental works until the mid-1630s, when he received three. In July 1634 he signed the contract for the tomb of Pope Leo XI. Leo XI, who belonged to a collateral branch of the Medici family, had died in 1605 after a reign of only 27 days, and his great-nephew, Cardinal Roberto Ubaldini (d. 1635), gave Algardi the commission.

The tomb, which is fitted skillfully into a narrow passageway in the north aisle of St Peter's and is composed to be seen at an angle from both sides, is similar in type to Bernini's tomb of Pope Urban VIII (1628), also in St Peter's. The statue of Leo XI enthroned is set into a niche above the sarcophagus, which is flanked by standing allegorical figures of Magnanimity and Liberality. Above the niche Leo XI's coat of arms is held by hovering putti. The sarcophagus is ornamented with a relief representing Cardinal de' Medici's Legation to France. The monument is, however, considerably smaller than Bernini's and is striking in that Algardi abandoned the combination of white and coloured marbles with bronze used by Bernini, preferring instead white marble throughout to underline the compositional simplicity of the work. The figure of Magnanimity is based on a classical Athena, for whose restoration Algardi had been responsible.

The tomb of Pope Leo XI was completed in 1644, and erected in 1652.