Practical guide
Plan without surprises
The Sforza commission
Leonardo worked in the refectory during the 1490s as part of Ludovico il Moro’s patronage. He transformed a traditional monastic subject into a scene focused on the announcement of betrayal and the apostles’ human reactions.
An experimental method
Instead of painting rapidly onto wet plaster, Leonardo used a dry preparation. The method enabled tonal modeling and revision but proved unstable. Historical accounts record deterioration within decades.
Damage and survival
Humidity, changing uses of the refectory, intrusive repairs, and a doorway cut into the wall altered the painting. In 1943 bombing destroyed part of the complex; the wall survived with protective measures already in place.
Modern conservation
The campaign led by Pinin Brambilla Barcilon from 1978 to 1999 removed later additions, consolidated the surface, and revealed readable fragments of original paint. Lost sections were not imaginatively reconstructed.