Cate Blanchett has given US talk-show king David Letterman a lesson in Australian history, displaying her sharp Aussie humour on the host’s popular late night show.

The Oscar-winning actress tore the host to pieces with her wit and charm when she appeared on The Late Show with David Letterman on Monday to promote her latest film, Blue Jasmine.

Blanchett told Letterman about her homeland’s geography and history when quizzed about her Aussie roots.

‘‘Are you, as an Australian, a subject of the Queen?’’ Letterman asked.

‘‘Officially, yes,’’ Blanchett replied.

‘‘How do you take to that in Australia?’’

‘‘Some people, not so well. But I have played a lot of queens and I live in Sydney where there are a lot of queens, so you know.’’

Blanchett proceeded to explain Aboriginal history and the formation of modern Australia following white settlement when Letterman later returned to the subject.

‘‘Tasmania ... is that part of Australia?’’ Letterman asked.

‘‘It is. Really, Wikipedia’s quite useful,’’ Blanchett answered, to much applause from the audience.

‘‘I know you’re all mocking my stupidity,’’ Letterman later told the crowd.

Dressed in a plunging black, stretchy dress purchased in Sydney, Blanchett spoke about the many Australian actors who’ve made the jump across the Pacific Ocean to Hollywood.

She went on to state: "Australia's a beautiful country. It’s God’s country - if you believe in God.

‘‘It’s tomorrow [there]. We’re ahead [of time]. We get everything first.’’

The Sydney-based actress has taken a hiatus from major film roles since taking on the co-artistic director’s chair at the Sydney Theatre Company in 2008, from which she and husband Andrew Upton are due to step down this year.

Having just finished her latest stage performance in the STC’s The Maids, the 44-year-old returns to the big screen in the Woody Allen-directed film Blue Jasmine, which opens in Australia in September.

Jokes aside, Letterman praised Blanchett’s performance in the film, in which she plays a pompous upper-east-sider on the brink of a breakdown after falling from high society.

‘‘You’ve taken a Woody Allen film and made it your own, which I think is virtually impossible,’’ Letterman said.

‘‘Because that man cannot direct, so someone has to lead the charge,’’ Blanchett joked.

 AAP

Correction: The original version of this story incorrectly said Blanchett spoke of the many Australian actors who made the jump across the Indian Ocean.

DailyStyle