You have probably already noticed how many paintings there are by Peter Paul Rubens. In the UK, in Spain, in the US, in Belgium, in the Netherlands, in Germany and sprinkled in many other countries. Surprising quantity.
How is that possible? The quick answer is, he did not paint them.
The longer answer is, he had a prosperous workshop. In his day, talented painters sold paintings under their names, that were painted by their employees. It was somewhat similar to today’s designer labels and brands.
Of course, early in his career, he painted. On special occasions, he would paint, like a portrait of his wife or the face
of a queen of somewhere. His assistants would paint the rest. Then, when he got tired of politics, travel, court life, in the last years of his life, he also painted a little.
What you have is a little bit at the start, a little bit during his decades of active life, a little bit at the end.
Everything else in between, which is most of it, was painted in the workshop. A superb workshop.
For these reasons, authenticating if a painting is by Rubens is more complicated than for most other artists because a “Rubens” can be and often is, the work of several painters.