Arness had a simple answer why Matt and Kitty's romance was never allowed to develop on screen: it would have changed the premise of the show.

"The idea was that Matt had this job he had to do, which was potentially a dangrous job, and you would have had a different show if he had been married and had kids," Arness told SCTV in Santa Clarita, California in 2006.

"I think, over the years, everybody realized that Matt and Kitty had a close relationship; they really cared for each other. But it just wouldn't have worked to have him be a married man with kids."

In the early seasons, it was implied that in addition to serving whisky and beer to thirsty cowboys, the Long Branch also operated as a brothel, with Miss Kitty acting as the madam. Viewers could see attractive young ladies entertaining cowboys in the background of numerous scenes. The effect was subtle enough to be ignored or missed by younger and naive viewers.
Classic TV Beauties
Classic TV Beauties 1960s Countdown
    AMANDA BLAKE as Kitty Russell in "Gunsmoke"
With her flaming red hair, big blue eyes and low throaty voice, Miss Kitty was the dream of every cowboy in Dodge City. The sexy proprietress of the Long Branch Saloon with the beauty mark was one of TV's original feminists: a tough, astute businesswoman who didn’t take gruff from any cowpokes in the old West.

The New York Times said Kitty was "the only woman character on nighttime television who is her own woman, successful in her own right and doesn’t bask in the reflection of some man.”

The first "adult Western," "Gunsmoke" practically created the genre for television. With a solid cast of Amanda, James Arness (Marshal Matt Dillon), Milburn Stone (Doc Adams), and Dennis Weaver (Chester) -- succeeded by Ken Curtis (Festus) -- "Gunsmoke" ruled network TV for most of its 20-year run.
Amanda starred in "Gunsmoke" for the duration of the series -- except the final season -- appearing in an amazing 425 episodes, a record for an actress on primetime TV.

Author Beckey Burgoyne, who penned Amanda’s biography (“Perfectly Amanda"), wrote of Kitty, “I was taken with her feisty strength, regal beauty, and of course, with Kitty’s mysterious relationship with Marshal Dillon.”

Oh yes. That mysterious relationship with Matt Dillon. The underlying inference throughout the series was that Kitty and the Marshal were a couple. The romance was suggested but never shown.

"We keep it very subtle," Amanda told United Press International in a 1962 article. "We let people let their imagination do what they want them to do. Actually, I love the scene where all we do is, as Jim says, 'eyeball it.'"
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"We never say it but Kitty is a prostitute, plain and simple," a "Gunsmoke" producer told Time magazine in 1961.

But Amanda told interviewer David Frost in 1973 that the morals of the show changed over the years: She wore less revealing costumes and the painted ladies-cowboy interactions pretty much disappeared.

"We always thought [that the idea of Kitty running a brothel] was interesting and very realistic and very adult. We used to show girls going up and down the stairs with cowboys… but that changed."

Kitty’s role was originally written as a smaller part; it expanded early in the series as she bought out the owner of the Long Branch and became a more integral character in the storylines.
In an interview with the Archive of American Television, Weaver succinctly summed it up as "the basic message was that there's going to be the bad and there's going to be the good. And most of the time, the good will win out."

Amanda was born as Beverly Louise Neill in Buffalo, and she moved with her family to Claremont, California when she was a teen-ager. She attended Pomona College but became so involved with theater productions she eventually left school to become an actress.

Nicknamed the “young Greer Garson,” she made her first appearance in the movie "Stars in My Crown" in 1950, and she appeared in about a dozen films during her career.

Because she stayed busy playing Miss Kitty, Amanda had little time to devote to other projects,

After 19 years of running the Long Branch, Amanda left the show following the 1974 season.
“Kitty started out as just one of the girls and we got some mail on it,” Amanda said. “The public realized that there was a relationship with Matt and Kitty, and they didn’t want Kitty available to the rest of the cowboys.”

Amanda had been a fan of the "Gunsmoke" radio program (1952-61) and felt she could play Miss Kitty. Without her persistance, she would've never gotten a chance to audition.

“I insisted on it,” she told Frost. “The producer had me mixed up with someone else and I became highly incensed over this so I proceeded to sit in his office until he saw me. He couldn’t avoid me.”

Amanda had one phobia to conquer, though, once she earned the role of Kitty: a fear of horses.
“I was terrified and crying,” she said. “A good friend of mine had been killed on a horse. Every time [the horse] took a step I screamed.

“Then at lunch, I had two scotch and waters. Within an hour I was trotting that horse up and down the set. After that I took lessons from a cowboy on the show.”

"Gunsmoke" was the longest running program (1955-75, 635 episodes) on primetime TV until "Law & Order" tied it in 2010. "Gunsmoke" was the No. 1 rated primetime network drama for four straight seasons (1957-61), drawing an astounding 43.1 rating one season,  and was a Top 10 show for 13 of the 19 seasons ratings were recorded.

Why was the series so successful?

“The chemistry between all of us was always extremely good. We like each other very much and that comes across on the screen,” Amanda said. She added that, “there are four completely different characters, a character for everyone to identify with.” 
“I was tired and it was time to go,” she said in a 1984 interview with the Los Angeles Times. “It was the end of the trail. I was locked in the saloon all those years. I figured there must be something else out there.”

Amanda was one of the first celebrities to die of AIDS when she passed in 1989 at age 60. The original cause of death for the two-pack a day smoker was listed as oral and throat cancer, but months after her death, Amanda’s doctor confirmed that she died of viral hepatitis, an AIDS-related illness.

“Amanda certainly had the biggest heart,” said Weaver. “A heart like a watermelon.”
Goldie Hawn "Rowan & Martin's Laugh In"
Amanda Blake "Gunsmoke" Kitty Russell
Amanda Blake "Gunsmoke" Kitty Russell
Amanda Blake "Gunsmoke" Kitty Russell
Amanda Blake "Gunsmoke" Kitty Russell
Elinor Donahue "Father Knows Best" Betty Anderson "The Andy Griffith Show" Ellie Walker
Joi Lansing "The Beverly Hillbillies" Gladys Flatt
Linda Kaye Henning "Petticoat Junction" Betty Jo Bradley
Susan Saint James "McMillan & Wife" Sally McMillan
Marlto Thomas "That Girl" Ann Marie
Barbara Eden "I Dream of Jeannie" Jeannie
Elizabeth Montgomery "Bewitched" Samantha Stephens
Donna Douglas "The beverly Hillbillies" Elly May Clampett
Doris Day "The Doris Day Show" Doris Martin