This Bull is one of the finest examples of Rubens' work with animals, this full portrait being completed around 1620. The artist took on animals common to Northern Europe at that time, such as cows, bulls and horses. Lions were also included, but would have been from a more contrived setting.
Some of these creatures would be depicted for the sheer value of individual artworks, whilst others would later appear within full scale oil paintings once the artist was confident in how he was capturing this element of the overall composition.
Businessman Rubens would later find out that engraved prints of his animal drawings would become very popular. By hiring the best local artists he could quickly sell on huge numbers of reproductions of his work and depictions of animals seemed to connect with mainstream art enthusiasts.
There was considerable research completed into Rubens' drawing around 2005, in partnership with an upcoming American exhibition. One exciting insight is that it appears Rubens took particular inspiration after viewing several Michelangelo drawings. He would later produce his own versions of some of these.
The majority of his drawings were produced as study pieces, essentially practice work in order to prepare correctly for a later artwork, typically either a painting, print, sculpture or architectural design. These different mediums made it necessary for him to alter his drawing style to match the type of work that it would later be used for.
Those with a specific artistic interest in the depictions of bulls would be wise to study the series of Bull drawings completed by Pablo Picasso in the 20th century.