At age 17, Williams joined the United States Merchant Marine and served until the end of World War II.

Moving to Los Angeles in 1943, the Williams Brothers sang with Bing Crosby on his 1944 hit record "Swinging on a Star".

She coached him, wrote his arrangements, and composed many songs that he recorded, including his 1958 top-20 hit "Promise Me, Love", and later, "Kay Thompson's Jingle Bells" on his 1964 number-one The Andy Williams Christmas Album.

Meanwhile, Williams sang backup on many of Thompson's recordings through the 1950s, including her top-40 hit "Eloise", based on her bestselling books about the mischievous little girl who lives at the Plaza Hotel in New York.

In the summer of 1961, Thompson traveled with Williams and coached him throughout his starring role in a summer-stock tour of the musical Pal Joey.

Their personal and professional relationship finally ended in 1962, after Williams met and married Claudine Longet, and Thompson moved to Rome.

Williams's third single, "Canadian Sunset", reached number seven in the top 10 in August 1956; it was followed in February 1957 by his only Billboard number-one hit, "Butterfly", a cover of a Charlie Gracie record.

Moon River and Other Great Movie Themes then sold across the country, garnering critical acclaim and propelling Williams into stardom.

In 1963, Williams's producer, Robert Mersey, encouraged him to record "Can't Get Used to Losing You" as the B-side to "Days of Wine and Roses".

Williams initially did not like the pop song, preferring the Mancini tune, but "Can't Get Used to Losing You" reached number two in the US and UK.

On August 5, 1966, the 14-story, 700-room Caesars Palace casino and nightclub opened in Las Vegas, Nevada, with the stage production of "Rome Swings", in which Williams starred.

On September 17, 1968, Columbia released a single of two songs Williams sang at the funeral of his close friend Robert F. Kennedy: "The Battle Hymn of the Republic" and Franz Schubert's "Ave Maria".

Williams also competed in the teen-oriented singles market and had several charting hits, including "Can't Get Used to Losing You", "Happy Heart", and "Where Do I Begin", the theme song from the 1970 blockbuster film Love Story.

In addition, Williams hit the top 10 of the UK Singles Chart with "Almost There" (1964), "Can't Help Falling in Love" (1970), "Home Lovin' Man" (1970), and "Solitaire" (1973).

The song "Happy Heart" was used for the final scene and end credits of Danny Boyle's award-winning directorial debut film Shallow Grave (1994).

In the early 1970s, when the Nixon administration attempted to deport John Lennon, Williams was an outspoken defender of the former Beatle's right to stay in the United States.

Williams performed during the halftime show of Super Bowl VII in January 1973, held at Los Angeles Memorial Coliseum.

[21] This led Williams to build his own theater in Branson in time for the 1992 season,[22] eventually opening on May 1, 1992, as the Moon River Theatre.

The Larson Company of Tucson, Arizona, fabricated a section of rock on Missouri's Highway 76 and the theater was soon engulfed with waterfalls, koi-filled ponds, ferns, and trees native to the Ozarks.

Frankenthaler, Diebenkorn, Oldenburg, Pollock, Klee, and Moore are on a small list of artists whose work is on display at the Moon River Theatre.

[25] Williams and his theater were featured on three episodes of the soap opera As the World Turns in July 2007, when several characters went to Branson for a concert of "Gwen Munson" held in the Moon River Theatre.

Nelson Muntz is an Andy Williams fan, and in the episode, he forces the gang to make a detour to Branson so he could see his idol.

In 2002, he re-recorded "Can't Take My Eyes Off You" as a duet with British actress and singer Denise van Outen; it reached number 23 in the UK singles charts.

In 1964, Williams ultimately became the owner of the Cadence master tapes, which he occasionally licensed to Columbia, including not only his own recordings, but also those of his fellow Cadence-era labelmates: the Everly Brothers, Lenny Welch, the Chordettes, Link Wray, and Johnny Tillotson.

Also in 1970, Barnaby signed and released the first album by an unknown singer-songwriter named Jimmy Buffett (Down to Earth) produced by Travis Turk.

Once Barnaby ceased operating as a working record company at the end of the 1970s, Williams licensed the old Cadence material to various other labels (such as Varèse Sarabande and Rhino in the U.S.) after 1980.

[37] In March 1976, Longet was charged with fatally shooting her boyfriend, alpine ski racer Spider Sabich, in Aspen.

Williams played a public role in the subsequent events, escorting her to and from the courtroom, testifying to her character at the trial, and providing legal assistance.

[47] After chemotherapy treatment in Houston, his wife and he moved to a rented home in Malibu, California, to be closer to cancer specialists in the Los Angeles area.

[49][50][51][52] Williams' body was cremated, and his ashes were sprinkled into the artificial waterway named Moon River at his theater in Branson.