This is the "A Seated Man with a Stick" painted by Rembrandt. Rather it is a study of a character type, dressed in an exotic costume intended to evoke an earlier era. Portraying figures in imaginary historical costume was common at the time. The light that sweeps across the painting from the left highlights one side of his face and shimmers on his silk cloak and the plume of his hat.
He makes an imposing figure, but this is probably not a portrait. Rather it is a study of a character type, dressed not in the fashion of his time but in an exotic costume intended to evoke an earlier era. The luxurious gold-coloured cloak or wrap has overtones of Turkish or Eastern Mediterranean styles.
Rembrandt painted several works like this one, including a self-portrait in Italian dress of 150 years earlier. The subject, the lighting and the use of colour in this painting is highly reminiscent of Rembrandt's work. However, most art historians now believe it to be a work by one of his students or imitators. X-ray images reveal that the figure has been painted over a rather roughly sketched image of the Crucifixion, suggesting that this was a piece of canvas on which a previous composition had been tried but then abandoned, before being re-used for this painting.
A Seated Man with a Stick hangs in The National Gallery on Trafalgar Square, London — free to enter. Point your phone at any artwork there and audioguide.london plays a free audio guide in six languages — no app download needed.