After sleeping for a thousand years, art woke up in Tuscany at the end of the thirteenth century. Giotto was the first great genius.
Giotto by Giovanni Dupré (1817-1882) Statue on the facade of the Uffizi Gallery (photo licensed under the Creative Commons Attribution-Share Alike 3.0 Unported, published here.)
There are a lot of stories about Giotto.
The most famous is his big O.
Pope Boniface VIII wanted to commission some paintings for St. Peter’s and so he sent a courtier around to find the best painter in Italy. The courtier asked all the artists to give him a sample of their work to send to the Pope. He came to Giotto’s workshop, explained his mission, and asked him for a drawing which would give the Pope some idea of his competence and style. “Sure,” said Giotto; and he laid down a sheet of paper, reached for a brush dipped in red paint, closed his arm to his side to make a sort of compass of it, and in one even sweep scribed a perfect circle. “There you are,” he told the courtier, handing it to him with a smile.
“That’s your drawing?” asked the courtier, who didn’t know whether Giotto was pulling his leg. “Is that all you’re going to send His Holiness?”
“That’s more than enough,” said Giotto. “Send it with your other drawings and see whether it’s understood or not.”
The Pope’s messenger took the drawing and went away trying to hold his temper. Did that little painter think he was a fool?
When he got back to Rome he showed the Pope the big O and told him how Giotto had scribed it—freehand, without a compass. The pope and his advisors DID understand the achievement of that O and gave Giotto the commission.
See Giotto’s Last Judgment in Little Nudes in Hell