Thurman, who appeared on The Late Show with Stephen Colbert, said she considers turning down that role as one of the "worst decisions" she ever made, reported Deadline.
"I would've played Eowyn in The Lord of the Rings," joked Colbert, a big fan of the franchise.
"It was a very long time ago, and I do consider it one of the worst decisions ever made. But I just had my first child and, I don't know, I was a little housebound. I think I was a little bit, it was a little unknown for me, but it's really definitely a regret," she said.