In a similar way to Head of an Old Woman, this is just a small canvas of around 28cm long by 20cm wide, having been cropped from an other canvas which perhaps had been damaged in the early years after Bosch's career came to an end. It is a little frustrating to not have the original piece to be able to see how this interesting portrait fitted into an overall composition, but there is still much to enjoy here none the less.
There are some clues as to what might have been before, for example the clear outline down the left hand side which suggests that this would have been placed into the corner of the original painting. There are also several items on his clothing and hat which give us an idea about his role in society. There is also a smart badge would could probably have been identified at that time, but would be difficult to do so now.
The overall portrait in terms of style, colour and attire is highly typical of the Northern Renaissance and Dutch Golden Age, where artist's studios would pass on ideas and techniques through the generations. They were able to consistently discover highly skilled artists such as Pieter Bruegel the Elder, Rembrandt, Jan Vermeer and Albrecht Durer who were able to continue this region's exceptional spell that lasted several centuries.
This small painting can be found amongst the huge collection of the Museo del Prado in Madrid whose most prominent work remains Las Meninas by Diego Velazquez. They also have further work from Hieronymus Bosch himself such as The Garden of Earthly Delights Triptych, The Adoration of the Magi Triptych, Extracting the stone of madness, Table of the Seven Deadly Sins and The Haywain Triptych. They actually term their own painting, Head of a Halberdier, as a Crossbowman.
Crowned with Thorns features a guard in the top left who is very similar to the crossbowman seen in this painting, at least in terms of his clothing, pose and the arrow that penetrates his hat. He is also on the left hand side of the painting, so perhaps our cropped portrait here is from another version or copy of the same painting.