Dudley Walker Morton (July 17, 1907 – October 11, 1943), nicknamed "Mushmouth" or "Mush", was a submarine commander of the United States Navy during World War II. He was commander of the USS Wahoo (SS-238) during its third through seventh patrols. Wahoo was one of the most-celebrated submarines of World War II, as it sank at least 19 Japanese ships, more than any other submarine of the time.^[1] Morton and Wahoo disappeared in 1943 during a transit of La Pérouse Strait. He was legally declared deceased three years later.

Morton was born in Owensboro, Kentucky, on July 17, 1907. He graduated from the United States Naval Academy in 1930. There he received the nickname "Mushmouth", after a character in the cartoon strip Moon Mullins whose large square jaw and prominent mouth resembled Morton's. The nickname was shortened to "Mush", by which he was known for much of his life.^[2] One of his classmates was Lance Edward Massey.

Prior to the outbreak of World War II, Morton served on the USS Saratoga (CV-3), USS Chicago (CA-29), USS Canopus (AS-9), USS Fairfax (DD-93), and the submarines USS S-37 (SS-142) and USS R-5 (SS-82), which he commanded from August 19, 1940, to April 23, 1942.^[3] Morton was promoted to lieutenant commander on October 15, 1942, and was in nominal command of USS Dolphin (SS-169) while it underwent extended repairs at Pearl Harbor. He was relieved to make a war patrol in USS Wahoo (SS-238) between November 8 and December 26 as prospective commanding officer, a supernumerary position to prepare him for command of a fleet boat. Morton took command of Wahoo on December 31 in Brisbane, Australia. Between January 26, 1943, and October 11, he carried out four offensive patrols, during which Wahoo was responsible for sinking 19 cargo and transport ships for a combined total of 55,000 tons.

With six war patrols, Morton ranked third among the Navy's top skippers, credited with 19 ships and 54,683 tons sunk, per JANAC^[13] (alternatively recorded as 17 ships/100,400 tons, per Blair^[14])

In 1960, Vice Admiral Charles A. Lockwood, Jr., ComSubPac during World War II, was asked to write the foreword for former Wahoo crewmember Forest Sterling's book, Wake of the Wahoo. He wrote about Morton: "When a natural leader and born daredevil such as Mush Morton is given command of a submarine, the result can only be a fighting ship of the highest order, with officers and men who would follow their skipper to the Gates of Hell... And they did." Added Lockwood: "Morton lined up an impressive number of 'firsts' during the short ten months that he commanded Wahoo: first to penetrate an enemy harbor and sink a ship therein; first to use successfully a down the throat shot; and first to wipe out an entire convoy single-handed."

In Herman Wouk's novel War and Remembrance, and the mini-series based on it, the Buyo Maru incident is prominently fictionalized as a scene for a major character's development.