After high taxation and a lack of representation drove the colonists to revolution, a war that would lead to the rise of a new nation broke out. Eventually Great Britain gave in and granted the Americans their independence and ended their war in the Treaty of Paris in November of 1782. As often people did when events of great significance took place, a painting was commissioned to commemorate the occasion, which was intended to be given to congress.
The painter commissioned was Benjamin West, who wanted to paint the representatives from life. The American representative obliged. The British representatives, however, refused to sit, symbolizing an American-British divide. Without Richard Oswald & Caleb Whitefoot, the painting could not be finished.
Information from: https://www.metmuseum.org/art/collection/search/656864