Lorenzo Ghiberti in the context of "Bronze sculpture"

Bernardo Cennini (Italian: [berˈnardo tʃenˈniːni]; 1414/15 – c. 1498) was an Italian goldsmith, sculptor and early printer of Florence. As a sculptor he was among the assistants to Lorenzo Ghiberti in the long project producing the second pair of doors—the Doors of Paradise—for the Battistero di San Giovanni. He produced the first book printed at Florence. The painter and author of a famous book on the crafts, Cennino d'Andrea Cennini, was a member of the same Florentine family.

Italian Renaissance sculpture was an important part of the art of the Italian Renaissance, in the early stages arguably representing the leading edge. The example of Ancient Roman sculpture hung very heavily over it, both in terms of style and the uses to which sculpture was put. In complete contrast to painting, there were many surviving Roman sculptures around Italy, above all in Rome, and new ones were being excavated all the time, and keenly collected. Apart from a handful of major figures, especially Michelangelo and Donatello, it is today less well-known than Italian Renaissance painting, but this was not the case at the time.

Italian Renaissance sculpture was dominated by the north, above all by Florence. This was especially the case in the quattrocento (15th century), after which Rome came to equal or exceed it as a centre, though producing few sculptors itself. Major Florentine sculptors in stone included (in rough chronological order, with dates of death) Orcagna (1368), Nanni di Banco (1421), Filippo Brunelleschi (1446), Nanni di Bartolo (1451), Lorenzo Ghiberti (1455), Donatello (1466), Bernardo (1464) and his brother Antonio Rossellino (1479), Andrea del Verrocchio (1488), Antonio del Pollaiuolo (1498), Michelangelo (1564), and Jacopo Sansovino (1570). Elsewhere there was the Siennese Jacopo della Quercia (1438), from Lombardy Pietro Lombardo (1515) and his sons, Giovanni Antonio Amadeo (1522), Andrea Sansovino (1529), Vincenzo Danti (1576), Leone Leoni (1590), and Giambologna (1608, born in Flanders).

Relief is a sculptural method in which the sculpted pieces remain attached to a solid background of the same material. The term relief is from the Latin verb relevare, to raise (lit. 'to lift back'). To create a sculpture in relief is to give the impression that the sculpted material has been raised above the background plane. When a relief is carved into a flat surface of stone (relief sculpture) or wood (relief carving), the field is actually lowered, leaving the unsculpted areas seeming higher. The approach requires chiselling away of the background, which can be time-intensive. On the other hand, a relief saves forming the rear of a subject, and is less fragile and more securely fixed than a sculpture in the round, especially one of a standing figure where the ankles are a potential weak point, particularly in stone. In other materials such as metal, clay, plaster stucco, ceramics or papier-mâché the form can be simply added to or raised up from the background. Monumental bronze reliefs are made by casting.

There are different degrees of relief depending on the degree of projection of the sculpted form from the field, for which the Italian and French terms are still sometimes used in English. The full range includes high relief (Italian alto-rilievo, French haut-relief), where more than 50% of the depth is shown and there may be undercut areas, mid-relief (Italian mezzo-rilievo), low relief (Italian basso-rilievo, French: bas-relief), and shallow-relief (Italian rilievo schiacciato), where the plane is only very slightly lower than the sculpted elements. There is also sunk relief, which was mainly restricted to Ancient Egypt (see below). However, the distinction between high relief and low relief is the clearest and most important, and these two are generally the only terms used to discuss most work.

Jacopo della Quercia (/ˌdɛlə ˈkwɛərtʃə/, Italian: [ˈjaːkopo della ˈkwɛrtʃa]; c. 1374 – 20 October 1438), also known as Jacopo di Pietro d'Agnolo di Guarnieri, was an Italian sculptor of the Early Renaissance, a contemporary of Brunelleschi, Ghiberti and Donatello.

The North Doors of the Florence Baptistery were made by Lorenzo Ghiberti between 1403 and 1424 and represent his first masterpiece, before the celebrated Gates of Paradise. The work is signed in the center, above the panels of the Nativity and the Adoration of the Magi: “OPVS LAUREN/TII•FLOREN/TINI.” After restoration in 2013-2015 (during which much of the original gilding was restored) the doors were displayed in the new Museo dell'Opera del Duomo and replaced by a copy.