This is the Equestrian Portrait of Charles I by Anthony van Dyck. Painted in about 1638-39, it's one of several portraits of Charles I that Van Dyck worked on. But this one stands out - it's the largest and most impressive.
Look at the King himself. He's surveying his kingdom, with a confident air about him. The gold chain around his neck is a symbol of his membership in the Order of the Garter, an elite society. And the baton he holds signals his senior military rank. In one hand, he calmly grips the reins to his powerful horse.
The horse itself is finely dressed, with gold decoration and elegantly styled hair. It's impressive, just like its rider. The Latin inscription on the tablet hanging from the tree identifies Charles as 'King of Great Britain'. A title that would soon prove ironic, given what was to come.
Charles I lost control of his state a few years after this painting was made, and was eventually put on trial for treason and executed. It's a poignant reminder of the power dynamics at play in this portrait. Van Dyck painted several portraits of Charles, but this one captures him at the height of his power.
Equestrian Portrait of Charles I 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.