Detail of the vault of the Chapel of St Sebastian in St Peter’s, Rome, cartoon

Another detail from the Chapel of St Sebastian vault cartoon from around 1633 by Pietro da Cortona documents his preparatory process for the St Peter's commission. These large-scale cartoons—full-size drawings used to transfer compositions to fresco—were essential working documents that reveal the artist's compositional thinking before the final execution. Cortona was the supreme master of Roman High Baroque decoration, whose ceiling fresco for the Gran Salone of the Barberini Palace defined the illusionistic ceiling painting that dominated European decorative art for a century. The Nationalmuseum in Stockholm holds this and the companion cartoon from the same commission, providing an unusually complete documentary record of Cortona's preparatory methods. Together they demonstrate his ability to conceive dramatic figural compositions at the monumental scale demanded by papal architectural patronage.

The cartoon reveals Cortona's confident draftsmanship and his ability to conceive dramatic figural compositions at monumental scale.