The Steam Ship Trident was built in 1841 by G.S.N. & Co. Packet steamers like the Trident were often used to ferry passengers long distances along the English Channel. The Trident also most likely carried King Albert and Queen Victoria on a trip from Scotland back to London, which this plate may have commemorated.
Sunderland, a coastal town on the eastern side of England, was known throughout the 13th - 19th centuries for its shipbuilding, and later in the 19th century for its pottery. Pieces were made with either local or imported clay, and decorated in a "lusterware" method (in which a metallic glaze produced additional shine). Sunderland pottery was handpainted, and metals such as copper, gold and platinum were often used in decoration. Depictions of people, places, and ships were most common.
