Michelangelo Buonarroti was commissioned by Pope Julius II in 1508 to repaint the vault of the Sistine Chapel. It was originally painted as golden stars on a blue sky. The work was completed between 1508 and 2 November 1512. Michelangelo was intimidated by the scale of the commission, and made it known from the outset that he would prefer to decline. He felt he was more of a sculptor than a painter. Eventually, though, he accepted the commission.
To be able to reach the ceiling, Michelangelo needed a support; the first idea was put forward by Pope Julius H's favoured architect Donato Bramante, who wanted to build a scaffold to be suspended in the air with ropes. However, Bramante did not successfully complete the task, and the structure he built was flawed. He had perforated the vault in order to lower strings to secure the scaffold. Michelangelo laughed when he saw the structure, and believed it would leave holes in the ceiling once the work was ended. He asked Bramante what was to happen when the painter reached the perforations, but the architect had no answer.
The matter was taken before the Pope, who ordered Michelangelo to build a scaffold of his own. Michelangelo created a flat wooden platform on brackets built out from holes in the wall, high up near the top of the windows. He lay on this scaffold while he painted.
(Adapted from http://en.wikipedia.Org/wiki/Sistine_Chapel#Ceiling)
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