Judith Thompson has become the first Canadian playwright to win the Susan Smith Blackburn Prize, a $20,000 US theatre honour.

Thompson was named winner at the award's 30th anniversary gala Monday night in Houston.

The Toronto playwright scored the prize for her critically acclaimed Palace of the End, which examines the U.S.-led invasion of Iraq from the viewpoint of three characters: a U.S. army reservist who takes part in abusing Iraqi prisoners, a British weapons inspector and an Iraqi political activist who survives torture under Saddam Hussein's regime.

Organizers hailed the play as "a theatrical Guernica, with each monologue taking the audience on a harrowing but somehow illuminating journey into the heart of this conflict."

Palace of the End concluded its run at Toronto's Canadian Stage in February. It is set to be performed off-Broadway by the Epic Theatre Ensemble beginning June 11.

Thompson, celebrated in Canada and an officer of the Order of Canada, had previously been a Blackburn Prize nominee for her play Habitat.

Monday's ceremony took place at Houston's Alley Theatre, where the namesake of the prize — performer, writer and educator Susan Smith Blackburn — began her theatre career.

Organizers also presented special commendations of $2,500 US each to three playwrights: Lisa McGee (Girls and Dolls), Jenny Schwartz (God's Ear) and Polly Stenham (That Face).

Established in 1978, the year after Blackburn's death, the prize annually celebrates a female playwright who has written an outstanding English-language work.