Walsh was born in Berkeley, California on November 2, 1931.^[1] He graduated with a bachelor's degree in engineering from the U.S. Naval Academy in 1954, and later, a Master's degree in political science from San Diego State University, and a PhD in physical oceanography from Texas A&M University.^[2]

Walsh attained the rank of captain by the time he retired. He spent fifteen years at sea, mostly in submarines, and was a submarine commander. He also worked with ocean-related research and development for the U.S. Navy.^[3][4]

Walsh was appointed as special assistant to the Assistant Secretary of the Navy for Research and Development from 1971 to 1972.

Serving as Dean of Marine Programs and Professor of Ocean Engineering at the University of Southern California, Walsh initiated and directed the university's Institute for Marine and Coastal Studies. In 1989, his company, International Maritime Incorporated, contracted a joint venture with the P.P. Shirshov Institute of Oceanology to establish an underwater maintenance company, Soyuz Marine Service, which continues to operate in the Russian Federation. Walsh continued to support ocean sciences in his work on the Ocean Sciences Board at the National Academy of Sciences.^[5] He managed a marine consulting business beginning in 1976, and as of 2010^[update] conducted about five deep-sea expeditions per year.^[6]

Walsh held a faculty appointment at Oregon State University in the College of Earth, Ocean, and Atmospheric Sciences.^[7][8]

It was reported in 2010 that Walsh visited the deep-sea submersible Jiaolong and its makers at the China Ship Scientific Research Center. The craft had "planted a Chinese flag on the bottom of the South China Sea during a two-mile-deep dive in June" as the Chinese program—which Walsh characterized as "very deliberate"—proceeded toward its ambitious goal of diving to 7,000 meters, or 4.35 miles, in 2012.^[9]

Walsh lived with his wife, Joan, in Sitkum, Oregon, on a ranch which they bought 1992. They had two children together. Walsh remained active with the National Academy of Sciences and the Ocean Elders organization.^[10][11]

Walsh was on-site to congratulate Victor Vescovo when he completed his own record-breaking series of dives in the Challenger Deep in 2019.^[12] In June 2020, Walsh's son Kelly dived to the bottom of the Challenger Deep with Vescovo, becoming the twelfth person to reach the deepest point in the ocean.^[13]

Walsh died at his home in Myrtle Point, Oregon on November 12, 2023, at the age of 92.^[1][14]

Walsh visited the wreck of the RMS Titanic on board the submersible MIR 2 on 20 July 2001.^[15]

Walsh joined the team that oversaw the dive of the Deepsea Challenger mission, during which James Cameron dived solo to the bottom of the Challenger Deep, on March 26, 2012.^[16]

Walsh was the inspiration for Chris Wright's 2015 book No More Worlds to Conquer, and his interview constitutes the opening chapter. The book, about moving on from the defining moment in one's life, was inspired by Walsh's answer to Wright's question, "What came next after the Trieste dive?" Walsh responded, "Well, a lot of people think I died."^[17]

Walsh was appointed by Presidents Carter and Reagan to the U.S. National Advisory Committee on Oceans and Atmosphere, was a member of the Law of the Sea Advisory Committee for the U.S. Department of State, and served as a member of the Marine Board of the U.S. National Research Council from 1990 to 1993.

In 2001, Walsh was elected to the National Academy of Engineering.^[18]

Walsh was named one of the world's great explorers by Life magazine.^[2]

On April 14, 2010, The National Geographic Society awarded its highest honor, the Hubbard Medal, to Walsh. The U.S. Navy awarded Walsh its Distinguished Public Service Award.^[19]

On September 22, 2020, The Marine Technology Society and The Society for Underwater Technology announced that the inaugural recipient of their new MTS/SUT Captain Don Walsh Award for Ocean Exploration was Edith Widder.^[20]

Recognitions include the following:^[21]

Legion of Merit citation edit

Citation:

The President of the United States of America takes pleasure in presenting a Gold Star in lieu of a Second Award of the Legion of Merit to Lieutenant Don Walsh, United States Navy, for exceptionally meritorious conduct in the performance of outstanding services from January 1959 to January 1960 as Officer-in-Charge of the Bathyscaph Trieste. Throughout this period, Lieutenant Walsh exercised marked professional skill and resourcefulness in carrying out an important assignment. During deep-diving operations in the Marianas Trench, he successfully completed a series of record-breaking dives, culminated by a dive to the unprecedented depth of 37,800 feet on 23 January 1960.^[22][23]

• List of people who descended to Challenger Deep

• Walsh, Don (June 2001). "Over the Top: Sailing the Northeast Passage". Proceedings. United States Naval Institute.(subscription required)
• Walsh, Don (January 2005). "The Plastic Ocean". Proceedings. United States Naval Institute.(subscription required)

• "Captain Don Walsh, USN (ret) PhD". Oceancareers.com. Centers for Ocean Sciences Education Excellence (COSEE).
• "A Tea for Marta" (PDF). The Explorers Club Northern California Chapter. June 2008. Archived from the original (PDF) on 2011-07-10.