Did Michelangelo really paint the Sistine Chapel lying on his back?

No: he stood. Michelangelo's own biographers, Giorgio Vasari and Ascanio Condivi, both say he painted the Sistine Chapel ceiling standing up, with his head tilted backwards, not flat on his back as another biographer, Paolo Giovio, imagined. Vasari put it bluntly: the frescoes were done with the greatest discomfort, because Michelangelo had to stand there with his head tilted back.

He did not even want the job. Michelangelo thought of himself as a sculptor, not a painter, and tried to push the commission onto his young rival Raphael. Pope Julius II was persistent, egged on, according to Vasari, by the architect Bramante, and Michelangelo signed the contract in May 1508 for a fee of 3,000 ducats, roughly 600,000 dollars in gold in 2021 terms. He then clashed with Bramante over the scaffolding: Bramante's design hung from ropes threaded through holes in the ceiling, which would have forced Michelangelo to paint around the gaps, so he had his own freestanding scaffold built instead.

He had planned to hire trained fresco painters to help him, but could not find anyone good enough, so he ended up painting the whole ceiling alone. It shows in how the work unfolds: his first scenes, starting with the Drunkenness of Noah, are cramped with smaller figures because he misjudged how big the ceiling really was. As he got the hang of it, his figures grew bolder and bigger, and by the end he could finish an entire scene, the last one, showing God in the act of creation, in a single day.

The ceiling, with its more than 300 figures, took four years, from 1508 to 1512. When it was finally uncovered, Vasari wrote that people rushed from everywhere just to see it, left speechless by the sight alone. Michelangelo was 37, and from then on people called him 'il divino', the divine one.