Sometime between the mid-1470s and his death in 1519, Leonardo da Vinci sketched a horse. On the same page, he jotted down his thoughts on a famous bronze stallion he'd admired in Pavia, likely capturing the moment he dreamed up the equestrian monument to Francesco Sforza that he would spend years planning and never complete.
Toward the end of the 16th century, a collector cut the page apart, and the two halves began very different journeys. The drawing eventually found its way to Windsor Castle, while the words landed in Milan, and for some 400 years, the horse and the thought behind it sat in separate countries, unable to explain each other.
Now they're back on the same page — digitally, at least. On June 8, 2026, Museo Galileo in Florence, together with the Italian Ministry of Culture and the Embassy of Italy in London, launched Leonardotheka, a free online platform that reunites roughly 3,500 pages of Leonardo's manuscripts for the first time since the late 16th century, undoing one of the century’s most consequential cut-and-paste jobs.
“His work embodies the unity of art and science, imagination and observation, creativity and reason. Therefore, projects such as Leonardotheka have such a crucial importance that extends well beyond academic research,” Fabio Cassese, Italy's ambassador to the U.K., said in a press release.
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How Leonardo da Vinci’s Manuscripts Were Cut Apart
When Leonardo died, his final student, Francesco Melzi, inherited a lifetime of notebooks, decades of anatomical studies, flying machines, landscapes, and grocery-list-adjacent musings, all tangled together the way Leonardo's mind may have worked.
That tangle didn't survive him as the papers passed to Italian sculptor Pompeo Leoni, who decided the pages needed organizing, so he cut the folios apart and sorted them into two albums, one for science and engineering and the other for art.
The system was tidy, but Leonardo had likely never intended to separate art from science in the first place. A single page might hold a machine, a horse, and a poem, and Leoni severed connections the artist had made on purpose.
The two albums then drifted apart. The scientific volume, a 1,119-sheet giant later known as the Codex Atlanticus, arrived at Milan's Veneranda Biblioteca Ambrosiana in 1637. The artistic album, around 550 sheets of figurative, anatomical, and landscape drawings, sailed to England in the 1620s and entered the Royal Collection by the 1680s, probably as a gift to Charles II.
Reuniting the Codex Atlanticus and Windsor Pages
Stitching the collections back together took a 10-year effort by Leonardo scholars and digital experts, working with Royal Collection Trust, the Ambrosiana, and the Biblioteca Leonardiana in Vinci. The team matched watermarks, sheet dimensions, and ink to determine which fragments had once belonged together.
The result includes 50 confirmed reconstructions, pages digitally restored to how Leonardo left them.
“This innovative tool marks the beginning of a new and highly promising era of research into the artistic, scientific, and literary legacy of the Genius of Vinci," Paolo Galluzzi, president emeritus of Museo Galileo and the platform's creator, said in the release.
Seeing Leonardo’s Art and Science Together Again
Anyone with an internet connection can now search across both collections, filter by watermark or drawing technique, and read transcriptions and commentaries.
The deeper opportunity is to see Leonardo the way he most likely saw himself. The world had sorted him into two figures, the painter and the engineer, but that sorting began with Leoni's albums, not with anything Leonardo did.
Leonardo never got to cast his bronze horse. The page where he first dreamed it up, though, has outlasted the dream itself, and after four hundred years, it is finally back in one piece.
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Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
- This article references information from Ambasciata d'Italia a Londra: Leonardo da Vinci writings and drawings reunited after 400 years in new digital platform
- This article references information from Museo Galileo: Leonardotheka 2.0 online from Monday, June 8
