He used the subtitle Valparaiso to create a rough idea of the time the image was created and its subject, i.e., the Spanish invasion of Chile's harbour in March 1866. James Whistler created this painting from memory. At the time, his primary goal was to capture the overall effect, not the accuracy of detail. Though the Americans sent an iron-clad battlement ship along with five steamers and the frigates and gunboats from the British and French troops, James only captures the sailing vessels. He aimed to display the sailing ships with some of them moving towards the open sea as others unfurled their sails.
James also captures the French tricoloured flag, though vaguely, against the gathering purple and violet clouds. A striking feature about this image was the way Whistler showcases the sleepy motion of the vessels as they retreated and seemingly breathing surface of the sea. According to J.Eddy’s book, which focuses on Whistler's creations, the artist completed Crepuscule in Flesh Colour and Green painting in one sitting as he had prepared all the required colours in advance. During this period, the Spanish occupation was happening in the Peruvian-owned islands, and the South American countries of Ecuador, Bolivia and Chile had formed an alliance to assist Peru. As a result, Whistler had left London for South America to support the Chilean cause. He arrived in Chile on March 12th when a troop of six Spanish ships was blocking Peru’s main harbor, Valparaiso.
The French, American and British governments also sent out troops to protect its nationals and act as the neutral peacekeeping force. Spain had planned to invade the city on March 27th, but the presence of British, French and American fleets prompted its troops to withdraw. James Whistler created this picturesque to capture that moment, on the evening of 30th March. He had fled to the hills on horseback to get a better view of the action. Whistler also created other pieces like The Morning after the Revolution, the Grey and Silver: Old Battersea Reach, among other pieces during that period. They mainly depicted the prelude and aftermath of the invasion. The Crepuscule in Flesh Colour and Green: Valparaiso painting was first displayed at the French Gallery in 1867.
When considering the style and content used by Whistler in this painting, comparisons can be drawn with related artists such as Edouard Manet in Alabama and Kearsarge, The Kearsarge at Boulogne and Steamboat Leaving Boulogne. Years earlier was Turner's Fighting Temeraire, which contributed to the work of Claude Monet with artworks such as Impression, Sunrise.