Bernini was also a leading figure in the emergence of Roman Baroque architecture along with his contemporaries, the architect Francesco Borromini and the painter and architect Pietro da Cortona. Early in their careers they had all worked at the same time at the Palazzo Barberini, initially under Carlo Maderno and, following his death, under Bernini. Later on, however, they were in competition for commissions, and fierce rivalries developed, particularly between Bernini and Borromini.[8][9] Despite the arguably greater architectural inventiveness of Borromini and Cortona, Bernini's artistic pre-eminence, particularly during the reigns of popes Urban VIII (1623–44) and Alexander VII (1655–65), meant he was able to secure the most important commissions in the Rome of his day, the various massive embellishment projects of the newly finished St. Peter's Basilica, completed under Pope Paul V with the addition of Maderno's nave and facade and finally re-consecrated by Pope Urban VIII on November 18, 1626, after 150 years of planning and building. Bernini's design of the Piazza San Pietro in front of the Basilica is one of his most innovative and successful architectural designs. Within the basilica he is also responsible for the Baldacchino, the decoration of the four piers under the cupola, the Cathedra Petri (Throne of St. Peter) in the apse, the chapel of the Blessed Sacrament in the right nave, and the decoration (floor, walls and arches) of the new nave.