The Academy Award for Best Picture is often quite contentious. Whereas other categories may be more "obvious" or agreeable, Best Picture tends to generate enormous amounts of controversy and debate. There's obviously no accounting for taste, so what is great for one person may be boring or insipid for another. Furthermore, some of the more obscure winners, thematically, aren't necessarily accessible to all audiences, prompting many viewers and readers to say, "I've never even heard of that."

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Professional movie critics tend to love Best Picture winners, though, and it obviously comes with the territory. But that isn't always the case.

Green Book (2018) - 69

Viggo Mortensen eating KFC in Green Book, Mahershala Ali riding in back seat

Green Book is arguably the most controversial Best Picture winner of the decade. Starring Viggo Mortensen and Mahershala Ali, the story is inspired by a real-life occurrence in which the Black American jazz pianist, Don Shirley, toured the American South with his Italian bodyguard and driver, Tony Lip Vallelonga.

It was co-written and directed by Peter Farrelly, who is better known for his beloved comedies like Dumb and Dumber and There's Something About Mary. The movie received relatively good reviews, but many critics didn't think it Best Picture material.

Argo (2012) - 86

Ben Afflect in Argo stands in a circle of people reading scripts

Argo was another controversial Best Picture winner, owing mainly to its numerous historical inaccuracies. In particular, the movie was criticized for displaying a falsely pro-American story and downplaying the important roles that the Canadian, British, and New Zealand embassies played in the rescue.

But as a movie, Argo is both exceptionally made and terrifically exciting. The movie received particular acclaim (and Academy Awards) for its brilliant editing and writing. In a rare occurrence, the movie did not win Best Director - that went to Ang Lee for Life of Pi.

Birdman (2014) - 87

Michael Keaton as Riggan walking down in the street in Birdman while Birdman hovers behind him

With the full title Birdman or (The Unexpected Virtue of Ignorance), the movie stars Michael Keaton as Riggan Thomson, a washed-up and forgotten superhero actor who is trying to put on a Broadway play. The movie contains a certifiable who's who of a cast, including Emma Stone, Edward Norton, Amy Ryan, Naomi Watts, and Zach Galifianakis.

Birdman took home the awards for Best Cinematography, Original Screenplay, Director, and Picture, and was nominated for a further five awards - including acting noms for Stone, Norton, and Keaton.

The Shape Of Water (2017) - 87

Elisa and Amphibian Man kiss in The Shape Of Water

Perhaps one of the weirdest Best Picture winners of all, Guillermo del Toro's The Shape of Water concerns a janitor named Elisa who falls in love with an amphibian creature housed at the secret government lab in which she works.

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The movie was nominated for an astounding 13 Academy Awards, winning for Best Original Score, Production Design, Director, and Picture. Of particular note were the visuals and production design, with the movie inhabiting a very unique and beautiful 1960s aesthetic.

The King's Speech (2010) - 88

George giving his speech in The Kings Speech

The King's Speech ticks all the boxes for a typical Oscar winner. It's a period piece, it concerns a popular historical subject, it tells an uplifting story about courage and overcoming obstacles, and it contains a slew of seasoned performers guaranteed to secure an Oscar nom.

And secure it they did, with the movie generating three acting nominations (Helena Bonham Carter, Geoffrey Rush, and Colin Firth and Firth winning Best Actor). The movie also received praise for its visuals, production design, writing, and directing - the latter two taking home their own respective Academy Awards.

The Artist (2011) - 89

George and Peppy dances in The Artist

Despite its 89 Metacritic score and Best Picture win, The Artist arguably remains one of the most forgotten winners in recent years. The movie is filmed like a black and white silent picture of the 1920s, telling the story of an up-and-coming actress and her relationship with a silent film star.

Jean Dujardin became the first French actor to win Best Actor, and The Artist was the first French-produced movie to win Best Picture. Most of the acclaim went to the movie's technicality, with praise being centered around the visuals, sound design, costumes, and cinematography.

Spotlight (2015) - 93

The Spotlight unit stand in the Boston Globe office in Spotlight

Spotlight is based on the real-life story of The Boston Globe's Spotlight team, a group of Pulitzer Prize-winning investigators that uncovered instances of child sex abuse in the Roman Catholic church. Difficult subject matter aside, the movie earned widespread praise for its acting and writing, becoming the first movie on this list to crack 90 on Metacritic.

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It was also the first Best Picture winner in over 60 years (since The Greatest Show on Earth in 1952) to win only one other Academy Award (Best Original Screenplay).

12 Years A Slave (2013) - 96

A slave master, Michael Fassbender, screams at a slave, Chiwetel Ejiofor in 12 Years a Slave

This horrifying movie was based on the memoir of the same name written by Solomon Northup. Northup was a free man living in Washington, D.C. when he was kidnapped, taken to the Deep South, and sold into slavery. Northup is portrayed by Chiwetel Ejiofor, who earned a Best Actor nomination for his performance.

He was one of the movie's nine Academy Award nominations, but not one of its three wins. Those were Best Adapted Screenplay, Best Picture, and Best Supporting Actress for Lupita Nyong'o.

Parasite (2019) - 96

The Kim Family sitting on their floor in Parasite

Parasite set numerous records throughout the 2020 awards season. It was the first non-English language film to win Best Picture, the first South Korean film to be recognized by the Academy, the first non-English language film to win the Screen Actors Guild Award for Outstanding Performance by a Cast, and the first movie since 1955 to win both the Palme d'Or and the Oscar for Best Picture.

Put simply, Parasite will be remembered as a piece of movie history.

Moonlight (2016) - 99

Mahershala Ali as Juan, holding Chiron in the ocean

Like Parasite, Moonlight set many award records. It was the first LGBTQ+ related film and the first movie with an all Black cast to win Best Picture. Mahershala Ali was the first Muslim to win an acting Oscar, winning Best Supporting Actor.

Furthermore, Joi McMillon became the first Black woman to receive an Academy Award nomination for Best Editing. It currently sits at an unbelievable 99 on Metacritic, with 39 of the 53 collected reviews being perfect 10s.

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