On this site was also a house that the Detra family lived in, with a second smaller building furnished as a bedroom for an occasional visitor. Rumor has it that the "occasional" visitor was usually one of Al Capone's men and other mob members.

In 1939, police captain and commander of the vice squad, Guy McAfee, bought the club, renovated it and renamed it the 91 Club.

Theatre magnate R.E. Griffith, and his architect nephew, William J. Moore, saw the El Rancho Vegas in 1941, and decided there was room for another resort. They purchased five acres of land for $1,000 an acre including the 91 Club which occupied the property. Griffith put Moore in charge, but it was Griffith who was the driving force.

This being during World War II, finding building materials was a job in itself. They decided to incorporate the 91 Club building into their plans. They bought mines for electrical wiring and other materials, and since food was being rationed, they bought ranches and raised cattle for food and milk to be served at their resort. Moore had built the El Rancho Hotel/Theater for Griffith in Gallup, New Mexico, but they couldn't use that name in Las Vegas. The hotel's slogan, "The Early West in Modern Splendor" was taken seriously as it was Griffith's idea that Las Vegas was the last frontier, where freedom and the Western spirit abounded.

On October 30, 1942, Griffith's Hotel Last Frontier opened with Moore as Manager. Where El Rancho rambled like a motor court, the Last Frontier was a single sprawling building with a reported 3,700 trees, plants, and shrubs planted on the property. Several distinct but connected segments gave the appearance of a main street from an Old Western town. The Carrillo Room named for actor Leo Carrillo, the Cisco Kid's sidekick, was the octagonal tower that had been part of the 91 Club. In this room hung a large picture of Carrillo astride his horse. Griffith and Moore purchased many items from existing downtown casinos, such as an antique 40 foot mahogany bar with French beveled glass from the Arizona Club on Fremont Street which once housed Las Vegas' most fashionable house of prostitution.

The Last Frontier Village was also part of the hotel's complex. Robert "Doby Doc" Caudill, a millionaire gambler, started collecting Nevada antiques in 1914. Doc contracted the Village his collection and was the curator. Guests could also reserve the Frontier boat for fishing and water sports on Lake Mead.

On November 24, 1943, Griffith died but his dream lived on through Moore who made the resort a success and an asset to the community by hosting various charities, war benefits and the like.

Moore was one of the first people who hired planes to fly the entertainment as well as gamblers to his resort. He decided to book flights with a small airline owned by Kirk Kerkorian, the future owner of the International and MGM Grand.

Frontier was to be the mainstay for the world famous aviator Howard Hughes whenever he went to Vegas. Rumor has it that his love for Vegas was born and grew during his frequent stays at this resort.

Frontier’s "Little Church of the West" was Moore’s idea of Moore. It was built of California redwood and was an authentic replica of a little church built in a pioneer town in California. It was a quaint and romantic spot amid dramatic western surroundings, where many famous marriage ceremonies had been performed. It was also the only building on the Strip to be listed on the National Register of Historic Places.

Headliners appearing at the Last Frontier Hotel in 1950 included the Nick Stuart Orchestra (including vocalist Loraine Day and Marv Roberts, and it's vocal group call the Tele-Vaires), the Harmonicats, Victor Borge, Herb Jeffries, Liberace, Ronald Reagan, Phil Silvers, and the singing group, the Continentals.

At the time the Nick Stuart Orchestra played, there were five hotels on the (two-lane, soft shoulder)strip: Wilbur Clark's Desert Inn, the Dunes at which Peggy Lee was appearing, the El Rancho Vegas, The Last Frontier, and the Flamingo whose billing included an act with Max Baer and Maxie Rosenbloom, while the Spike Jones was the featured attraction.

In 1951, Moore left the Last Frontier when the stockholders decided to sell the resort to Jake Kozloff, 91 Club owner Guy McAfee, and Beldon Katleman of the El Rancho Vegas for $5.5 million. Kozloff felt that Las Vegas was no longer the "last" frontier, and changed its name to "The New Frontier" in 1955. The slogan was also changed to "Out of This World". Kozloff refurbished, and redecorated the interior to modern contemporary western decor, yet sustaining Griffith and Moore's old west theme by keeping some of the Hotel Last Frontier intact.

In 1954, a group of buyers that included Murray Randolph, a real estate executive from Los Angeles, Irv Leff, a Los Angeles businessman and Maurice Friedman purchased the Frontier from Kozloff and McAfee.

In 1956, the hotel was leased to German munitions heiress Vera Krupp, Louis Manchon and Sidney Bliss. Krupp and her partners didn't see eye to eye and they were losing money. In order to avoid being sued, she returned the property to the 1954 owners on St. Patrick's Day, 1957. The casino was closed down and operated the hotel as a motel until December of 1957, while they searched for a casino operator suitable for licensing. The resort was then leased to Warren Bayley who also owned the Hacienda Hotel & Casino. On In 1959, Frontier re-opened its casino to the public.

Some of the celebrities to perform at the resort during the 1940s & 50s included Sophie Tucker, Mandrake the Magician, Marx Brothers, Judy Garland, Ronald Reagan, Frank Sinatra, Sammy Davis, Jr., Eddie Albert & Margo accompanied by Jack Eastern, Jack Carter, Henny Youngman, Tommy Dorsey's band, and Josephine Baker.

In 1961, Frank Webster filed an application for 98% of the New Frontier. The Gaming Control Board deferred action on a recommendation on Webster's application, saying it was not ready. Bankers Life purchased the resort with President John D. MacArthur keeping the hotel closed until the summer of 1965. When he couldn't find a tenant to operate the hotel, he called Friedman asking to tear the old building down and build a new hotel. MacArthur authorized $6 million for the project. The Frontier Operating Company was formed involving new owners including Steve Wynn, who took over the lease from MacArthur and Bankers Life in June of 1967. Controversy arose when some of the owners were accused of mob affiliations. Apparently, Wynn didn't know this when he bought into the resort and got caught in the middle of the scandal.

Because of these allegations, coupled with lackluster management, New Frontier was about to go under. State authorities were gung-ho on ridding the mob reputation from the Strip and therefore contacted Howard Hughes, who was in the process of declaring his own war on the mob, regarding a possible purchase. On September 22, 1967, Hughes bought his beloved resort for $14 million from all owners and shortened the name to "The Frontier". Almost immediately after the purchase, The Frontier started turning a profit.

Some of the celebrities to perform at the resort during the 1960s & 70s included Frank Sinatra, Jr., Eddie Fisher & Abbe Lane, Mickie Finn Show, Bobby Darin, Jimmy Durante with Sonny King and Eddie Jackson, Phil Harris, Barbara McNair, Wayne Newton with Jerry Newton, Teresa Brewer, John Byner, George Carlin, Frank Gorshin, Robert Goulet, Bob Newhart, Diana Ross with Sammy Shore, Ronnie Shell, The Supremes, and Flip Wilson.

In 1980, the Little Church of the West was moved to the Hacienda resort.

Some of the celebrities to perform at the resort during the 1980s were Wayne Newton, Roy Clark and Siegfried & Roy.

Margaret Elardi, a past owner of the Pioneer in downtown Vegas, and the Laughlin Pioneer, bought The Frontier from a company that was once owned by Howard Hughes. On September 21, 1991, Frontier became a focal point for controversy when Elardi encountered problems with the unions. A 61 month strike ensued with 550 union workers. It became an eyesore of the Strip with strikers picketing and at times bothering people on the sidewalk as well as patrons of the hotel. The property's last collective bargaining agreement was negotiated in 1984. The Frontier strike began when hotel and casino workers represented by four unions left their jobs charging the hotel had cut hourly wages, slashed hotel and welfare benefits and eliminated contributions to their pension plan. Union workers from Culinary Local 226, Bartenders Local 165, Teamsters Local 995, and Operating Engineers Local 501, walked a picket line around the clock since the start of the strike.

In October, 1997, Wichita businessman Phil Ruffin purchased the Frontier for $167 million and agreed to a five year contract ending the strike. Ruffin's deal included an additional $3.5 million that went for the payment of wages owed to striking workers. In addition Ruffin decided to create a "New Frontier holiday" to be included in the holidays that the employees had off. This extra holiday is the day that the strike ended and is called "Labor Peace Day". In addition to the 986-room Frontier, which sits on 26 acres near the center of the Strip, Ruffin holds an option to buy a neighboring 16.5 acres of vacant land that was once home to the Silver Slipper Casino. Ruffin changed the resort’s name back to the New Frontier.

On January 5, 2000, it was announced that the Frontier was to close her doors forever. Ruffin announced that he was going to implode the Frontier and build a replica of San Francisco, California - a casino named City By The Bay which should be completed in September, 2002, containing 2,500 rooms at a cost of $700 million. Ruffin has 13 other hotels and he plans to use their cash flows to support the new project.

Mark Advent of Advent Communications and Entertainment who created the concept for New York-New York took legal action against Ruffin. Advent stated that he has been working with Ruffin for the past two years to create a San Francisco-themed megaresort, and copyrighted detailed plans, designs, concepts and other proprietary information with Ruffin, and Ruffin's agent Craig Dudley. Ruffin dismissed Advent's complaint stating "city themes are in the public domain.