The 1960s were certainly a different time for movies. The concept of the summer blockbuster had yet to be born, and without summer blockbusters, it was very hard to predict what movies would take off and which ones wouldn't. Unlike the modern era, in which the highest-grossing films of the decade are populated mainly by superhero films, the 1960s proved far more diverse and unpredictable.

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Some of the movies from the decade are epic adventures. Some are musicals, some are war films, and some are even historical dramas. Regardless, the 1960s were an exciting and incalcuable time in regards to box office performance.

1960: Spartacus

Two men about to fight in Spartacus.

Based on the 1951 novel by Howard Fast, Spartacus was directed by Stanley Kubrick and stars Kirk Douglas as the titular gladiator. Laurence Olivier also stars as the Roman general, Crassus.

The movie was an enormous success, and it reportedly grossed $17 million throughout its first year of theatrical release. When adjusted for inflation, this equates to just under $150 million today. The movie also took home four Academy Awards at the 33rd Academy Awards, including Best Supporting Actor for Peter Ustinov.

1961: West Side Story

Two characters speaking to each other in West Side Story

Back in 1957, West Side Story premiered on Broadway to incredible success. Four years later, the movie adaptation was released. Directed by Robert Wise and Jerome Robbins, West Side Story serves as a "modern" re-telling of Shakespeare's Romeo and Juliet using two gangs in New York's Upper West Side.

Upon its original release in 1961, West Side Story earned $19.5 million in the United States and Canada and $44 million worldwide. When adjusted for inflation, this amounts to $168 million and $380 million, respectively.

1962: The Longest Day

The Longest Day

Based on the non-fiction book of the same name, The Longest Day concerns the famous D-Day landings of World War II. The movie was a monumental epic that contained a certifiable who's who of 50s and 60s stars, including Henry Fonda, Robert Mitchum, John Wayne, and Sean Connery.

It's no surprise that the movie was such a success. The Longest Day became the highest-grossing black and white film at the time, taking in $30.5 million in theatrical rentals. Today, that's around $260 million.

1963: Cleopatra

Elizabeth Taylor nearly kissing Richard Burton in Cleopatra.

Released in June of 1963, Cleopatra remains one of the most popular movies to come out of the 1960s. Based on the book The Life and Times of Cleopatra, Cleopatra starred Elizabeth Taylor as the titular Egyptian ruler and Richard Burton as Mark Antony.

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It was the most expensive movie ever made at the time, produced at a cost of $31 million (about $260 million today)! Luckily for Fox, the movie was a major success, grossing just under $58 million in the United States and Canada. Today, that equates to just under $500 million - a staggering amount for the domestic market.

1964: Mary Poppins

Julie Andrews plays the iconic Mary Poppins

Perhaps the most famous movie musical ever made, Mary Poppins was released to incredible fanfare in the late summer of 1964. Based on the children's books by P.L. Travers, Mary Poppins concerns a magical nanny who aids a dysfunctional family in Edwardian London. The movie served as Julie Andrews's movie debut, and it made her a worldwide star.

Mary Poppins took in $31 million throughout its original domestic release, accounting for roughly $260 million in today's dollars.

1965: The Sound Of Music

The Sound Of Music

In 1961, West Side Story set the record and became the highest-grossing musical in movie history. But it only held the record for four years before The Sound of Music shattered it in 1965. Again starring Julie Andrews (giving her back-to-back highest-grossing films of the year), The Sound of Music spent over 40 weeks in the top box office position - a streak that lasted well into 1966.

By November of that year, the movie had taken in $125 million in gross receipts (nearly $1 billion today), breaking the record for the highest-grossing movie of all time.

1966: Hawaii

Hawaii Julie Andrews

Julie Andrews continued her incredible streak with 1966's Hawaii - giving her back-to-back-to-back number one films of each respective year. In this movie, she plays Jerusha Bromley Hale, the new bride to Max von Sydow's Reverend Abner Hale. Hale serves as a missionary in the Hawaiian islands who attempts to convert the "natives" to Calvinism.

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The movie likely coasted on its exotic Hawaiian locale and star power of Julie Andrews. It ended up grossing $15.6 million in the United States and Canada - about $125 million today.

1967: The Graduate

Dustin Hoffman Benjamin Braddock The Graduate

The Graduate is one of the most famous movies to come out of the 1960s, and it remains one of the decade's most popular and culture-defining outputs. This isn't one of those dramas that had a slow start before accumulating a devoted fanbase through home video and repeated TV airings. No, this was a massive success from the get-go.

In the domestic market, The Graduate grossed approximately $104 million in its original box office run. Today, this would account for a staggering $805 million! Those are numbers generally reserved for Star Wars, not an introspective drama about aimless college graduates.

1968: Funny Girl

Funny Girl 1968

Loosely based on the life and career of comedienne Fanny Brice, Funny Girl stars Barbra Streisand as Fanny Brice and Omar Sharif as professional gambler and con artist, Nicky Arnstein.

Streisand won the Academy Award for Best Actress (for her film debut, no less), and Funny Girl proved enormously popular with mainstream audiences. It grossed an approximate $58.5 million throughout 1968 - just over $430 million today. It was no Sound of Music, but it was an incredible success, nonetheless.

1969: Butch Cassidy And The Sundance Kid

The final shot of Butch Cassidy and the Sundance Kid

Widely known as one of the finest Westerns in movie history, Butch Cassidy and the Sundance Kid was released to wide acclaim and enormous popularity in the fall of 1969. The movie is loosely based on the real story of Butch Cassidy, real name Robert LeRoy Parker, and the Sundance Kid, Harry Longabaugh. Both were Old West outlaws and train robbers.

The movie had made $15 million by the end of 1969 ($105 million today) and eventually finished its initial run with $46 million in rentals ($325 million today).

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