In the very first shot of the opening credits, the American flag over the harbor can be seen flying at half-mast. The reason was the assassination of President John F. Kennedy, shortly before the shot was filmed.
In the first-season credits, Russell Johnson and Dawn Wells were relegated to being simply "the rest". That changed in the second season when Bob Denver demanded that they be given an equal share in the credits, thus changing the lyrics to "The Professor and Mary Ann". Sherwood Schwartz, who composed both themes, has said it didn't occur to him the Professor and Mary Ann would turn into prominent characters.
The ship's name, S. S. Minnow, was not named for the fish but rather for Newton Minow, head of the Federal Communications Commission in 1961. Minow was the one who called television "America's vast wasteland". Sherwood Schwartz did not care for Minow so he named the soon-to-be shipwrecked ship after him, though he later said that Minow actually enjoyed the joke and that the two eventually exchanged regular friendly correspondence.
Alan Hale Jr. had a tendency to address people as "little buddy". Because of this, "little buddy" became the Skipper's signature term of affection for Gilligan. It is now widely used by fans as a nickname for Bob Denver.
Alan Hale Jr. was on location in Utah filming a movie when he got a call to come back to Los Angeles to do a test for the series. He rode a horse to a nearby highway, hitchhiked to Las Vegas and flew to L.A. to test with Bob Denver.
Sherwood Schwartz said he had a first name for Gilligan if the need to use it ever arose: Willie. This name is never spoken on screen, so it seems as if Gilligan only has one name as with celebrities such as Homer or Cher.
The first season had the cast using cups that were made from real coconuts. However, they found that the cups were porous and soaked through like they were sweating. Thus in the later seasons, the coconut cups were ceramic replicas.
"The radio" seen in virtually every episode was a Packard-Bell AM Radio, Model AR-851. The small silver handle and telescoping antenna were added by the prop department (despite the fact that AM radios do not use telescoping antennas). The antenna was likely added to lend credence to the castaways' ability to pick up radio signals so far from civilization.
As the show progressed, producers planned to introduce a new character--a pet dinosaur--but decided against it because of the cost of special effects. The character, however, was incorporated into the animated Gilligan's Planet (1982).
Four vessels were used as the SS Minnow. One was towed to Kauai, Hawaii, for beach scenes, one was rented in Honolulu for the original opening credits and one was built at CBS Studios in the second season. The fourth one was used in the second-season opening credits. A subsequent owner was sailing it south from Alaska when it ran aground on a reef off the coast of British Columbia. It was purchased for salvage and restored. It was offered for sale in B.C. for $99,000. It was listed as a 37-foot twin-diesel, mahogany Wheeler Express Cruiser which sleeps five.
Natalie Schafer's contract stipulated that there be no close-ups of her in the show. The reason was producers knew her real age, which was 13 years older than Jim Backus, who played her character's husband. It was not until years after the series ended that her co-stars found out her actual age.
The premise required that the characters use various devices that had to be constructed from only the various materials found on a tropical island. Thus the props had to be specially made and the prop department enjoyed the challenge, which was a change of pace from simply bringing in the standard props from storage. The bamboo foot pedal-powered car used in one episode was a particular favorite, with the cast lining up to try it out.
Dawn Wells, who played Mary Ann, was terribly tone deaf. Whenever she sang, even if it was just a song like "For He's a Jolly Good Fellow", her off-key singing would throw everyone else off. Singer/songwriter Jackie DeShannon dubbed Mary Ann's singing voice for most of the times the character had to sing (an exception was Gilligan's Island: The Second Ginger Grant (1967), where Mary Ann's inability to sing was part of the plot).
The show was originally slated to return for the 1967-68 television season along with another new comedy show to replace the canceled "Gunsmoke" (1955)_. However, CBS reversed its decision and canceled "Gilligan" and kept "Gunsmoke", which ran for another eight seasons.
With the show ready to go to air, Sherwood Schwartz had yet to come up with a theme song. When it came time for him to submit one, he decided to make the theme a story of how the characters got shipwrecked. It was then titled "The Ballad of Gilligan's Island".
At one point during development, producers considered including a young nephew of the Professor's among the castaways. However, it was determined that given the child-like nature of Gilligan, a child among the castaways would be redundant.
Partly inspired by the 1939 film Five Came Back (1939) starring Lucille Ball. The characters in that film included a wayward pilot and co-pilot, a botanist and his wife, a sultry woman with a shady past, and a rich playboy and his homespun wife.
The name "Ginger Grant" is believed to be taken from two stars of Hollywood's "Golden Era", Ginger Rogers and Cary Grant; the latter is frequently spoken of in this series. "Ginger" is a nickname in many places (including England) for someone with red hair.
Natalie Schafer said she initially did "Marooned" (1962), for the free trip to Hawaii. Afterwards, Schafer was in Puerto Vallarta, Mexico, on holiday when she got a telegram from the US. She read it and burst into tears. Everyone had thought Schafer's mother (who was ill at the time) had died, and offered their condolences, but Schaefer said her mother hadn't died; the reason she was crying was because the pilot for "Gilligan's Island" sold, and she had to stay in Los Angeles, and could not move back to New York City.
The original series pilot Gilligan's Island: Marooned (1992) had different actors in the role of the Professor and two female castaways, Ginger and Bunny, both secretaries. Because of the cast changes, the original pilot was unairable until it was broadcast by TBS in 1992.
Although it is a widespread belief that American television in the 1960s was not allowed to show women's navels, such anatomy is seen frequently in this series. Mary Ann's navel in particular is most commonly shown, but also occasionally that of Ginger, and some bit player guest stars and extras. Supposedly the producers discovered a loophole in the rules to allow this. In fact, the prohibition against showing a woman's navel was over by 1966.
One of the most burning questions among male viewers of the show has always been, "Ginger or Mary Ann?". Though there is no real answer to that question, the consensus seems to be that Dawn Wells got more fan mail from young boys, while Tina Louise got more fan mail from grown men. The difference is attributed to the fact that Mary Ann was the pretty and sweetly sexy girl next door that every teenage boy would love to go out with, while Ginger was the gorgeous, smoking-hot sex bomb that is every adult male's fantasy.
The producer and main cast all lived to advance ages. Sherwood Schwartz lived to be 94 and Natalie Schafer (Lovey Howell) lived to 90. The shortest longevity was from Alan Hale Jr. (the Skipper), who died at 68. Bob Denver (Gilligan) died at 70, Russell Johnson (the Professor) died at 89. At the 50th anniversary on September 26, 2014, only two cast members still survived, Tina Louise (Ginger Grant) and Dawn Wells (Mary Ann). The two ladies were 80 and 75 years old, respectively. Also, three of the cast members died within 21 months of each other. Jim Backus (Mr. Howell) died in July 1989 at 76, the first of the cast to pass away. Six months later Alan Hale Jr. passed away, followed by Natalie Schafer 15 months later. Another actor would not die for more than 14 years later: Bob Denver.
Sherwood Schwartz claimed that, contrary to popular belief, "Robinson Crusoe" was not the inspiration for the series, even though it was one of his favorite books and was referenced in the closing song.
Jim Backus' name of Thurston Howell III was named after "Hubart Updyke III", a character on "The Alan Young Show" on radio, written by this series' producer, Sherwood Schwartz--and also played by Backus..
Of the seven castaways, the Skipper is known for breaking the fourth wall, i.e. looking directly into the camera and making a face. However, Ginger would occasionally do this as well, in particular, right after she tries to kiss Gilligan and he resists, usually knocking himself out. She then looks at the camera and shrugs.
It is revealed in Gilligan's Island: Two on a Raft (1964), (the second pilot) that the name of Mary-Ann's hometown was Winfield, Kansas. It is sometimes misreported as Horner's Corners, but that was the home of her boyfriend, Horace Higgenbotham.
Each of the three actresses on Gilligan's Island were married only once and their marriages were fairly short term. Natalie Schafer (Mrs. Howell) was married nine years, Dawn Wells was married five years, and Tina Louise was married four years.
It has often been observed that although they were on "a three-hour tour," the castaways have an awful lot of supplies. Mary Ann and Ginger have seemingly not ever worn the same clothes twice, the Professor has an extensive library, the Howells have myriad luxury items, etc. It has also been observe that although the Professor could build all sorts of intricate, complicated machinery from the few resources available on the island, he apparently never thought to just patch up the hole in the side of the Minnow so everyone could just sail off the island..
The original script had Ginger as a more seductive character, willing to use her sex appeal to get what she wanted, and Mary Ann as a naive country girl. When 'Tina Louise' (qv was cast as Ginger she played the character as a more sweet-natured, innocent individual who seldom used her sex appeal for her own gains. Because they felt it was too similar to the original version of Mary Ann, that character was rewritten to be more level-headed and logical.
There has long been a rumor that Alan Young was originally supposed to be Gilligan, due to the fact that series creator Sherwood Schwartz had produced Young's comedy series on the radio, whose character was similar to that of Gilligan, and also because Jim Backus' character of Thurston Howell III was based on the same kind of character--also played by Backus--on Young's show. However, in an interview, Schwartz said that Young was never considered for the role. It came down to Bob Denver and another actor, who had an opportunity to make either this pilot or one for another series and chose the other pilot, which resulted in Denver being cast as Gilligan.
When Alan Hale Jr.played the part of "the Skipper", he referred to Gilligan as " little buddy" on a regular basis. Alan Hale Jr. also played a guest role on The Andy Griffith Show as farmer "Big Jeff Pruitt" in Season 2 episode 13: "The Farmer Takes a Wife", prior to Gilligan's Island. In that episode, he referres to Don Knotts's character Barney Fife, as "little buddy" on several occasions as well.
In January 2016, shortly after the deaths of musicians David Bowie and Glenn Frey, an obituary from CBS News began getting attention. The hashtag #RIPBobDenver began trending along with #RIP tags for Frey and Bowie, so many users of social media thought Denver had passed away along with Bowie and Frey, when in fact Denver had died in 2005.
Before playing the skipper of the Minnow, Alan Hale Jr. played the engineer of the Cannon Ball Express in the series Casey Jones (1957). Russell Johnson (The Professor) appeared as a guest in that series.