Admiral Harriman Nelson was a fictional character first played by Walter Pidgeon in the 1961 science fiction movie, Voyage to the Bottom of the Sea, and later played by Richard Basehart in the 1964-1968 TV series of the same name. Both the movie and the series were set in the near-future of the 1970s and 1980s, with the series generally using dates between 1973 and 1984. Since this era was depicted from the vantage point of a decade earlier, their version of the decade obviously differs considerably from the one that actually took place.
In both versions, Nelson is a four-star admiral (though at the beginning of the TV series, he was shown to have three-stars and no explanation was ever given as to when, how, or why he obtained his fourth star), and one of the world's most brilliant scientific minds. He's cited as being "One of the world's foremost marine biologists" in both versions, and also apparently holds high degrees in Nuclear Physics as well. The TV series added that he was also one of the brightest minds in computer engineering alive at that time. He also won the Nobel prize in Biology for 1976 (as explained in the episode, Cyborg).
Nelson retired from the active-duty Navy at some point prior to the beginning of the series (And movie), and formed the Nelson Institute of Marine Research, which is headquartered in Santa Barbara, California. In this capacity, he designed and built the 400+ foot Seaview (later designated as SSRN in the TV series), which is the world's only privately-owned-and-operated Nuclear Submarine. Nelson also developed the process for the transparent hull plating - ' X-tempered Herculite ' - for the ' window ' sections of the sub's forward nose. With it, he hoped it would afford ' sights never before seen by Man, and by seeing, solve some of the mysteries of the deep '. The USOS Seaview (for United States Oceanographic Survey, & in the motion picture, under the Bureau of Marine Exploration) is, however, listed as a Naval Reserve vessel, and is automatically drafted into active service as the US Navy deems necessary. As such, her crew is composed entirely of retired or reserve naval personnel.
Nelson has always felt it was his duty to be strictly apolitical, and refused to ever voice an opinion publicly on a political matter. In the second season, however, he was forced to take a different stance when he discovered that a leading candidate for Secretary of Defense was actually an enemy agent. Despite his apoliticism, Nelson is extremely close friends with fictional US President Henry Talbot MacNeil, and was counted as one of the president's poker buddies.
Nelson's religious beliefs are a subject of some debate. He is obviously a rational - if moody - intellect, and clearly believes in evolution; however, he has also memorized lengthy passages of the Bible, which he recites on occasion, and he seemed condescending towards a visiting Soviet dignitary's vocal atheism on at least one occasion. That said, despite his several paranormal experiences, Nelson appears, on balance, to be Deistic or else guardedly irreligious.
A closer look at the "text" - i.e. the actual episodes - suggests a decidedly Christian bent to the Admiral's complex personality. As noted above, Nelson frequently quotes Scripture, "Cradle of the Deep (1965)", "Jonah & the Whale (1965)". More examples tend to indicate the Admiral's familiarity with Scripture went beyond that of simply a well-read man. In "The Cyborg (1966)," he flashes a clearly disgusted look at a mad genius who had quoted Genesis 1:27 to glorify his own creative work (that being a race of synthetic "humanoids.") In both "Jonah & the Whale" and "The Terrible Toys (1967)," he suggests prayer to a Soviet scientist and Crane (respectively) on occasions of dire peril. In two burials at sea - one for a "People's Republic" officer in "The Exile (1965)" and another for ghostly U-Boat Capt. Krueger in "The Phantom Strikes (1966) - Nelson and his friend Capt. Lee Crane refer to "the Resurrection" and their belief "those who call on the name of the Lord shall be saved." It is certainly true, however, that Nelson's religious/Christian denomination - if he had one - was never mentioned in the television series.
The list below contains all of Nelsons's known awards and decorations. The names are given in order of precedence, according to SECNAVINST 1650.1F and the U.S. Navy Uniform Regulations (NAVPERS 1566.5G).