The self-conscious, often witty play with the rules of classical architecture that followed the High Renaissance: triglyphs that slip, pediments that break, columns sunk in walls and stairs that pour like lava: a style for connoisseurs who knew the rules well enough to enjoy their violation.
By the 1520s the vocabulary of ancient architecture had been mastered, and the generation after Raphael began to treat it as material for invention. The term Mannerism, borrowed from painting (maniera, style), covers a range of attitudes rather than one manner: the elegant complication of Giulio Romano, the brooding sculptural force of Michelangelo, the learned codification of Vignola and Serlio.
Giulio Romano’s Palazzo Te in Mantua (1524–34), built for Federico Gonzaga’s pleasure, is its manifesto. In the courtyard a triglyph of the Doric frieze drops out of place at intervals, as if the stones were slipping; keystones burst up through pediments; rustication and smooth ashlar are mixed as if the building were half finished. Michelangelo’s vestibule to the Laurentian Library in Florence (1524–71) sinks paired columns into the wall so that they appear to carry nothing, sets blind windows between them, and fills the floor with a stair of three flights whose central steps curve and spill downward.
Michelangelo also invented forms that later architects would use seriously: the giant order (The giant order) of the Capitoline palaces, the broken and layered pediments of the Porta Pia, the vigorous drum and ribbed dome of St Peter’s. Vignola’s church of Il Gesù in Rome (1568) and its front by Giacomo della Porta set the model for the Counter-Reformation church (The two-storey church front) and lead directly into the Baroque.
North of the Alps, where the orders arrived through Serlio’s woodcuts and Flemish pattern books, Mannerism took the form of richly ornamented gables, strapwork and grotesque ornament on buildings that were often still Gothic in plan. The period also saw the engineers’ geometry of the bastioned fortress and the planned star town of Palmanova (1593) (The bastioned trace).