Speaking with reporters, the two -- who play lovers set in 1950s New York -- detail their impression of the film, with Blanchett saying it expertly avoided being deemed "political," due to its homosexual themes.
The 46-year-old actress said timing helped Carol be seen for what it is: a love story. "I think the landscape around the conversation around same-sex relationships has advanced in a lot of countries," the Australian star said. "The universality of the love story comes to the fore, rather than any sort of political agenda."
She also explained the "relief" she felt when filming intimate scenes with her co-star Mara. "Both characters are quite isolated," she said. "Not only because their feelings set them apart from others, but the gap in their ages. They go through these volcanic feelings toward one another so it was a relief to do the scenes with Rooney. Finally, we get to be together."
Mara, who plays the younger lover, a store clerk named Therese Belivet, revealed chemistry between herself and Blanchett was natural. "Chemistry isn't something you can create," she told reporters at the festival. "As in real life, you either have it or you don't. I felt lucky that it was easy for me to feel chemistry towards Cate."
Wearing a light-colored, delicately ruffled Alexander McQueen dress, Mara's look complemented that of her co-star Blanchett -- who donned a black and white gown by Esteban Cortazar -- on the red carpet Wednesday night.
Blanchett also took a moment to dispel earlier comments she made to Variety in May discussing real-life intimate relationships with women. At the time, she said she has had "many" relationships with women.
"If I was playing someone who had an affair, I think there would be a moment of pause before a journalist asked me how many affairs I have had," she said, according to BT. "And if I was playing an axe murderer, they wouldn't necessarily ask me how many people I've murdered."
"I probably answered in a way that was a bit facetious and they took it literally. No offense, but I'm busy and I've got four kids."
Directed by Todd Haynes, Carol is scheduled for release in U.S. theaters Dec. 18.