The 86-year-old Czech film director will be best remembered for making 'One Flew Over The Cuckoo's Nest' and 'Amadeus', which is considered to be one of the greatest movies of the 1980s.
He also directed 'The People vs. Larry Flynt', 'Hair', and 'Man on the Moon with Jim Carrey and Danny DeVito. His last film was 'Goya's Ghosts' back in 2006.
In his home country, Forman made 'The Firemen's Ball' and 'Loves of a Blonde' back in the 1960s before his career literally took off when he went over to the USA to make 'Taking Off' in which he hit the ground running by winning the main prize at Cannes.
Here's some of the tributes being paid on Twitter:

Milos Forman has left us. Genius of cinematography and master in the portrayal of the human condition. RIP pic.twitter.com/pLcXIeEH9h

— Antonio Banderas (@antoniobanderas) April 14, 2018

Film lost one of its great true visionaries yesterday - Milos Forman. I will always be grateful to him for telling my story in The People vs Larry Flynt. He was a remarkable man with extraordinary talent. I will miss his presence on this earth.

— Larry Flynt (@ImLarryFlynt) April 14, 2018

One Flew Over the Cuckoo’s Nest is one of my favorite films of all time. Blatantly steal from it in #Glass. Milos Forman was a true artist.

— M. Night Shyamalan (@MNightShyamalan) April 14, 2018

Very sad to hear that the great director Miloš Forman has passed away. He had a tremendous filmography that documented the rebel heart and human spirit. I have seen 'One Flew Over The Cuckoo's Nest' enough times to be able to silently mouth along with the movie. RIP. pic.twitter.com/4QwOHL7tS4

— edgarwright (@edgarwright) April 14, 2018

Another great one passes through the doorway. Milos Foreman. What a force. A lovely man. I’m glad we got to play together. It was a monumental experience. ;^) pic.twitter.com/wzgmOibDHs

— Jim Carrey (@JimCarrey) April 14, 2018

Proof that the most brilliant of filmmakers could also be unfailingly kind, generous, humble and loyal. Thank you Milos Forman pic.twitter.com/btUmryxjRr

— Mia Farrow (@MiaFarrow) April 14, 2018

Milos the magnificent! čest k jeho památce (honour to his memory) light a good cigar, raise a drink, and shout “HOVNO HOVNO HOVNO!

— Danny DeVito (@DannyDeVito) April 14, 2018

One of the world’s truly great movie makers. RIP #MilosForman check out his filmography & see one of his movies this weekend to honor him. https://t.co/YLev5CS2jk

— Ron Howard (@RealRonHoward) April 14, 2018

Golden Globe-winning director Milos Forman has died at the age of 86. He was known for films including One Flew Over The Cuckoo's Nest, Amadeus, The People vs Larry Flynt, and Man on the Moon. Rest in Peace. pic.twitter.com/dJrMUj9MwB

— Golden Globe Awards (@goldenglobes) April 14, 2018

I still remember the rare images of black life in the early 1900s offered in RAGTIME. Saw it as a teen and recall crying. Howard Rollins, Debbie Allen, Moses Gunn. Directed by Milos Forman. He made many films I enjoy. But I’ll be rewatching RAGTIME today. In appreciation. #RIP pic.twitter.com/QOC1lSvzX7

— Ava DuVernay (@ava) April 14, 2018

We lost one of our great filmmakers with the passing of Milos Forman. It's time to solve the music rights issues & release a Blu ray of one of his greatest works: TAKING OFF - one of the most accurate portraits of the USA circa 1971 as it could only be interpreted by an outsider. pic.twitter.com/8hEJbPyWs8

— Joe Dante (@joe_dante) April 14, 2018

So sad to hear of the passing of legendary director Miloš Forman. The world has lost one of the great filmmakers. No one combined masterful storytelling with extraordinary images like Miloš. Feel privileged to have known him a little bit. Our condolences to his family. RIP pic.twitter.com/7TxRZ3YX3V

— Cary Elwes (@Cary_Elwes) April 14, 2018