The best actor award was given to Ireland's Colin Farrell for his part in the tragicomedy The Banshee Of Inisherin while All the Beauty and the Bloodshed, a documentary about US photographer Nan Goldin and her fight against the wealthy Sackler family, won the top Golden Lion award on Saturday.
Made by investigative journalist Laura Poitras, All the Beauty and the Bloodshed interweaves the remarkable story of Goldin's own life with her campaign to hold the Sacklers and their pharmaceutical company accountable for the US opioid crisis.
"Thank you so much, it's such an enormous honour," Blanchett said, having just flown back to Venice from the Telluride Film Festival where the film also played.
Her performance as a successful woman in the world of international music whose reputation comes under threat has gotten nearly universal acclaim.
"I'm shocked to get this and thrilled," Farrell said in a live video message broadcast at the festival on Saturday night.
The runner-up Silver Lion award went to an intense French courtroom drama Saint Omer by director Alice Diop making her debut in fiction after a string of documentaries.
Luca Guadagnino won the Silver Lion award for best director for the cannibal romance Bones and All starring Timothée Chalamet and Taylor Russell, who also was recognised for her performance for best young actress.
"I have a speech prepared because I'm nervous," Russell said.
"I'm grateful beyond belief to be standing here. So many of my heroes are in this room."
Russell thanked Guadagnino.
"He's been a great friend to me and I love him so dearly," Russell said.
The jury also gave a special jury prize to No Bears by imprisoned Iranian director Jafar Panâhi.
The acclaimed director was in July ordered by Iran to serve six-year prison sentence from a decade ago that had never been enforced.
The order came as the government seeks to silence criticism amid growing economic turmoil and political pressure.
Julianne Moore led the jury that selected Saturday's winner from a pool of 23 films in competition that included many Oscar hopefuls.
The Oscar-winner presided over a jury that included French director Audrey Diwan, whose film Happening won the Golden Lion last year, author Kazuo Ishiguro (Never Let Me Go) and Iranian actor Leila Hatami (A Separation).
Also on the main jury were Italian director Leonardo Di Costanzo (The Inner Cage) Argentinian filmmaker Mariano Cohn (Official Competition) and Rodrigo Sorogoyen (The Candidate).
Premiering in competition at Venice has launched many successful Oscar campaigns in recent years, leading to nominations and even wins.
Seven times in the last nine years the best director Oscar has gone to a film that world premiered at the festival, including Chloé Zhao, Alfonso Cuarón, Alejandro G. Iñarritu, twice, Guillermo del Toro and Damien Chazelle.
It has also debuted a handful future best picture winners like Nomadland, The Shape of Water and Birdman.
with AP
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