[8] Giorgio Vasari described Giotto as making a decisive break from the prevalent Byzantine style and as initiating "the great art of painting as we know it today, introducing the technique of drawing accurately from life, which had been neglected for more than two hundred years".

Almost every other aspect of it is subject to controversy: his birth date, his birthplace, his appearance, his apprenticeship, the order in which he created his works, whether he painted the famous frescoes in the Upper Basilica of Saint Francis in Assisi, and his burial place.

[11] Since 1850, a tower house in nearby Colle Vespignano has borne a plaque claiming the honor of his birthplace, an assertion that is commercially publicized.

[1] In his Lives of the Most Excellent Painters, Sculptors, and Architects Vasari states that Giotto was a shepherd boy, a merry and intelligent child who was loved by all who knew him.

[14] The story about the fly is also suspect because it parallels Pliny the Elder's anecdote about Zeuxis painting grapes so lifelike that birds tried to peck at them.

When the messenger related how he had made the circle without moving his arm and without the aid of compasses the Pope and his courtiers were amazed at how Giotto's skill greatly surpassed all of his contemporaries.

[16] The Archbasilica of St. John Lateran houses a small portion of a fresco cycle, painted for the Jubilee of 1300 called by Boniface VIII.

The documents of the Franciscan Friars that relate to artistic commissions during this period were destroyed by Napoleon's troops, who stabled horses in the Upper Church of the Basilica, so scholars have debated the attribution to Giotto.

In the 1960s, art experts Millard Meiss and Leonetto Tintori examined all of the Assisi frescoes, and found some of the paint contained white lead—also used in Cimabue's badly deteriorated Crucifixion (c. 1283).

[18] The authorship of a large number of panel paintings ascribed to Giotto by Vasari, among others, is as broadly disputed as the Assisi frescoes.

[20] Earlier attributed works are the San Giorgio alla Costa Madonna and Child, now in the Diocesan Museum of Santo Stefano al Ponte, Florence, and the signed panel of the Stigmatization of St. Francis housed in the Louvre.

[25] Enrico degli Scrovegni commissioned the chapel to serve as family worship, burial space[26] and as a backdrop for an annually performed mystery play.

The frescoes are more than mere illustrations of familiar texts, however, and scholars have found numerous sources for Giotto's interpretations of sacred stories.

[28] Vasari, drawing on a description by Giovanni Boccaccio, a friend of Giotto's, says of him that "there was no uglier man in the city of Florence" and indicates that his children were also plain in appearance.

"[9][16] The cycle is divided into 37 scenes, arranged around the lateral walls in three tiers, starting in the upper register with the story of St. Joachim and St. Anne, the parents of the Virgin, and continuing with her early life.

The central allegories of Justice and Injustice oppose two specific types of government: peace leading to a festival of Love and tyranny resulting in wartime rape.

They are solidly three-dimensional, have faces and gestures that are based on close observation, and are clothed, not in swirling formalized drapery, but in garments that hang naturally and have form and weight.

Of Giotto's realism, the 19th-century English critic John Ruskin said, "He painted the Madonna and St. Joseph and the Christ, yes, by all means... but essentially Mamma, Papa and Baby".

[32] Numerous painters from northern Italy were influenced by Giotto's work in Padua, including Guariento, Giusto de' Menabuoi, Jacopo Avanzi, and Altichiero.

It is now thought that he produced the design for the famous Navicella mosaic for the courtyard of the Old St. Peter's Basilica in 1310, commissioned by Cardinal Giacomo or Jacopo Stefaneschi and now lost to the Renaissance church except for some fragments and a Baroque reconstruction.

According to Vasari, Giotto remained in Rome for six years, subsequently receiving numerous commissions in Italy, and in the Papal seat at Avignon, but some of the works are now recognized to be by other artists.

[35] It is a large painting (325 × 204 cm), and scholars are divided on whether it was made for the main altar of the church, where it would have been viewed primarily by the brothers of the order, or for the choir screen, where it would have been more easily seen by a lay audience.

The Bardi Chapel depicts the life of St. Francis, following a similar iconography to the frescoes in the Upper Church at Assisi, dating from 20 to 30 years earlier.

Previously ascribed to Giotto, it is now believed to be mostly a work by assistants, including Taddeo Gaddi, who later frescoed the chapel.

Also in this time period, according to Vasari, Giotto composed a series on the Bible; scenes from the Book of Revelation were based on ideas by Dante.

[46] After Naples, Giotto stayed for a while in Bologna, where he painted a Polyptych for the church of Santa Maria degli Angeli and, according to some sources, a lost decoration for the Chapel in the Cardinal Legate's Castle.

[47] In The Divine Comedy, Dante acknowledged the greatness of his living contemporary by the words of a painter in Purgatorio (XI, 94–96): "Cimabue believed that he held the field/In painting, and now Giotto has the cry,/ So the fame of the former is obscure.

During an excavation in the 1970s, bones were discovered beneath the paving of Santa Reparata at a spot close to the location given by Vasari but unmarked on either level.

[48] While the Italian researchers were convinced that the body belonged to Giotto and it was reburied with honour near the grave of Filippo Brunelleschi, others have been highly sceptical.

[49] Franklin Toker, a professor of art history at the University of Pittsburgh, who was present at the original excavation in 1970, says that they are probably "the bones of some fat butcher".