Top image: The Everett Collection

Just sit right back and you'll hear a tale…

In September of 1964, the S.S. Minnow first set out on its fateful trip as Gilligan's Island premiered on American television sets. Few could have predicted the cultural impact of the lighthearted sitcom. Beginning in black & white, the Sherwood Schwartz creation blossomed into full color in its second season. In some ways, it was like a living cartoon, which was part of its charm and appeal.

Today, Gilligan, the Skipper, Mary Ann, Ginger, the Professor and the Howells remain household names, as do the actors who portrayed the seven castaways. To celebrate this loveable slice of television history, here are some things you might not know about Gilligan's Island. Grab a coconut and kick back.

1. The original castaways included "two secretaries." The pilot episode differed greatly from the final product. Most notably, the characters included "two secretaries" and a "high school teacher," as the wildly different theme song announced. The pilot, titled "Marooned," was so different, it was not aired at the time, though it eventually hit television in 1992. Image: Warner Bros.

2. Star Wars composer John Williams wrote the original calypso theme song heard in the pilot. The first theme song mentioned above was a jaunty, hokey calypso number sung by Sherwood Schwartz himself in a Caribbean patois. The tune was composed by John Williams (who went by Johnny Williams at the time) would of course go on to soundtrack immortality with his work for Star Wars and Steven Spielberg. Here are some more early television works of Williams. Image: AP Photo/Charles Miller

3. Jerry Van Dyke turned down the role of Gilligan. Van Dyke turned down an offer to play Gilligan in 1964 because he didn't want to be part of an ensemble cast. The younger Van Dyke brother wanted to replicate the success of his older brother Dick and have his own TV show. The opportunity came one year later, when he nabbed the lead in the short-lived My Mother the Car. He might regret the decision now, but we're happy the part eventually went to Bob Denver. Image: NBC via Wikimedia Commons

4. JAYNE MANSFIELD, CARROLL O'CONNOR and DABNEY COLEMAN were almost castaways, too. Can you imagine Archie Bunker as the Skipper? Or Raquel Welch as Ginger? It almost happened! Read more about the Gilligan's Island cast that almost was.

5. Six women have played Ginger. Tina Louise perfectly portrayed the bombshell starlet, though she was not exactly enamored with the role. In subsequent spin-offs and sequels, other actresses stepped in to play Ginger. Initially, in that pilot, Kit Smythe filled the role, though as we have noted the character was a secretary. After Louise stepped away from the island forever, she was replaced in later TV movies by Judith Baldwin (Rescue from Gilligan's Island, The Castaways on Gilligan's Island) and Constance Forslund (The Harlem Globetrotters on Gilligan's Island). In the 1974 animated series The New Adventures of Gilligan, Jane Webb voiced Ginger, while in the 1982 cartoon Gilligan's Planet, Dawn Wells handled both Mary Ann and Ginger!

6. The flag in the opening credits is at half-mast because of the Kennedy assassination. The pilot was filmed in November 1963. On the final day of production in Hawaii, the cast and crew learned of John F. Kennedy's assassination. There is a small, subtle reminder of this historical incident seen on the series. In the opening credits of the first season, as the Minnow pulls out of the harbor, the United States flag can be seen flying at half mast.

7. THE SKIPPER'S REAL NAME WAS JONAS GRUMBY, AND HE SERVED WITH JFK AND MCHALE. His character's name Jonas Grumby is mentioned in the pilot, though it is hardly uttered again. Speaking of JFK, the postmodern 2003 novel Gilligan's Wake, which is not officially tied to the show, crafts a backstory for the Skipper that explains he served on a PT with both Kennedy and Quinton McHale of McHale's Navy. It may not be official, but we like to believe it to be true.

8. GILLIGAN'S FIRST NAME IS WILLY. Yes, trivia buffs, Gilligan has a first name and it's not Gilligan. According to Schwartz, it is Willy.

9. The S.S. Minnow was jokingly named after the head of the FCC. Newton Minow was the chairman of the FCC who had infamously described television as "a vast wasteland." That's a nice little industry in-joke.

10. Charles Maxwell was the uncredited voice on the radio. The castaways are constantly tuning in to news with their portable radio. The announcer heard is the voice of Maxwell, a veteran character actor who appeared on Bonanza, Gunsmoke, Lawman, Rawhide and The Rifleman. Though he was never credited, Gilligan's Island was his longest recurring role.

11. It was originally a "six hour ride," not a "three hour tour." Oh, one more key difference between the pilot and the series. In the first theme song, the lyrics tell of a "six hour ride." Somewhere along the way in the creative process that itinerary was cut in half. Image: The Everett Collection

12. The band that sang the familiar theme song also sang "The Ballad of Davy Crockett." The first version of the "The Ballad of Gilligan’s Isle," a ditty written by Schwartz with George Wyle, was sung by the Wellingtons. The folk-rock act also performed "The Ballad of Davy Crockett" heard in the Disney miniseries Davy Crockett. The Gilligan's theme would eventually be changed to include the Professor and Mary Ann as their characters grew in importance and fandom. The first version merely referred to them as "the rest." Image: Disneyland Records / Discogs

13. The Wellingtons also appeared as the Mosquitoes on the show. Though their take on the theme song was no longer being used, the Wellingtons did get to physically appear on the show in the second season episode "Don't Bug the Mosquitoes," when they washed up as the Beatles parody the Mosquitoes.

14. The childless Howells suddenly have a son in 'The Harlem Globetrotters on Gilligan's Island.' It is told on the original series that Lovey and Thurston produced no offspring. However, in the third and final (and bizarre) reunion movie The Harlem Globetrotters on Gilligan's Island, Thurston Howell IV (David Ruprecht, host of the game show Supermarket Sweep) is included in the cast. This was due to the poor health of Jim Backus, though the original Thurston did put forth a valiant effort to briefly appear in his weakened state.

15. Martin Landau and Barbara Bain last appeared together in 'The Harlem Globetrotters on Gilligan's Island.' While we're on the topic of that goofy TV movie, here's another historical footnote. The married duo of Landau and Bain, who had appeared together on Mission: Impossible and Space: 1999, costarred in that basketball crossover. The 1981 production would be the couple's final performance together. They divorced in 1993. Image: NBCUniversal Television Distribution

16. Sherwood Schwartz also made a western knockoff of 'Gilligan's Island' called 'Dusty's Trail.' After Gilligan's Island, Schwartz hit the jackpot again with The Brady Bunch. However, the third time was not a charm. In 1974, the creator-producer attempted to recreate Gilligan's Island in a Wild West setting. The result was Dusty's Trail, which also starred Bob Denver alongside Forrest Tucker of F Troop fame. The wagon train also included a rich couple, a brainiac, a farm girl and a bombshell. The show tanked after one season, though four episodes were stitched together to make the theatrical release The Wackiest Wagon Train in the West. Image: The Everett Collection

17. Tina Louise and Bob Denver were in a beach movie together before 'Gilligan's Island.' Months before Gilligan's hit the airwaves, Denver and Louise costarred in the summer surf flick For Those Who Think Young. The teen comedy also featured Nancy Sinatra and Ellen Burstyn. Here are 10 more fascinating facts about Tina Louise. Image: The Everett Collection

18. The location of the island is 250 miles SE of Hawaii. Probably. Just where is the island exactly? Three somewhat specific locations are given throughout the three seasons. In "'X' Marks the Spot," the island's position is said to be approximately 140º latitude by 10º longitude. (Which are impossible coordinates.) Later, in the episode "Big Man on a Little Stick," their position is stated as approximately 110º longitude by 10º latitude. (Assuming that to be negative 110º, that would put the island a ways off Mexico's Pacific coast. Finally, in "It's a Bird, It's a Plane," the U.S. Navy spots Gilligan flying over the island in a jet pack. They give the location as 250 miles south of Hawaii. So, 10º latitude, -140º longitude would make the most sense for that location. Image: The Everett Collection

19. The 'Gilligan's' cast once impersonated the 'Roseanne' cast. Tina Louise did eventually reunite with her Gilligan's costars in an unlikely place — Roseanne. It was a bit of a homecoming, as the two shows filmed on the same sound stage. The episode "Sherwood Schwartz—A Loving Tribute" even had the castaways slip into the roles of Roseanne characters, as seen in this still, with Louise playing Roseanne, Dawn Wells as Darlene… and Bob Denver as Jackie! Image: SFM Entertainment

20. ALAN HALE, JR., PLAYED A CHEF NAMED GILLIGAN ON 'BATMAN.' In the episode "The Ogg and I," one featuring Vincent Price as Egghead, the Police chief enters a diner and sidles up to the counter. The cook comes out and it is Alan Hale. The chief says to him, "Right, Gilligan, one large milk and a hot pastrami." Check out more fascinating facts about Alan Hale, Jr.

21. THE CITY OF DENVER IS NAMED AFTER BOB DENVER'S GREAT-GREAT-GRANDFATHER. The Colorado capital was named for James William Denver, the great-great-grandfather of Bob Denver. And, no, Bob is not related to John Denver, who was born Henry John Deutschendorf, Jr. Here are more things you might not know about Bob Denver.