Rubens had several paintings in his career where he would begin work on them before taking a long break of several years and then returning to complete them. Prometheus Bound was one of those - initially started around 1611 before finally being finished around seven years later. This is likely down to the artist's personal interest and enthusiasm around this particular work as he was to keep it in his own collection for many years after it was finished.
The cruel tale of Prometheus was how he was chained to a rock and pecked at by wild birds as punishment for steeling fire from the gods in order to benefit humanity. The wrath of Zeus was strong and to be feared. The continual cycle of pain followed by regeneration has a somewhat Hellish feel to it, with these powerful emotions being sufficient inspiration for most artists.
Frans Snyders painted the eagle within this painting and at this time in the Flemish regions collaboration was very common between respected artists. Synders himself was best known for paintings of animals as well as still-lifes and Rubens was happy to allow him to contribute here. Several artists have built a reputation for stunning depictions of animals, most of all perhaps George Stubbs, who went to extraordinary lengths to ensure anatomical accuracy.
The Philadelphia Museum of Art in Pennsylvania, USA is an impressive institution with some highly significant artworks within its permanent collection. They cover many different topics, such as Asian art, weaponary, armour and paintings from the Renaissance all the way up to movements like Cubism and Modernism.
The highlights from this museum include Pieta by El Greco, Epiphany by Hieronymus Bosch, The Burning of the Houses of Lords and Commons by William Turner, The Battle of The Alabama and Kearsarge by Edouard Manet and Japanese Bridge and Water Lilies by Claude Monet. It is also significant to find this Rubens painting there, as most of his work remains in Europe often in the countries where he produced them.