The cause of death was cancer, friends said. The Pittsburgh Post-Gazette reported that Mr. Lamberts, 63, had battled prostate cancer, throat cancer and complications.
Mr. Lamberts was a major star in Canadian theatre who also worked south of the border in regional theatre, on Broadway and in TV ("Law & Order" and "Remember WENN," among other appearances).
His work as Cyrano de Bergerac at the Shaw Festival in Ontario led to him being awarded the Order of Canada in the 1980s.
Shaw's former artistic director, Christopher Newton, told Playbill.com Mr. Lamberts was "one of the great comedians, one of the best of actors. He helped to put the Shaw Festival on the map when he played Cyrano de Bergerac in the early '80s."
In the United States, he played the antsy, neurotic butler-timepiece, Cogsworth, in the Houston world premiere of the stage version of Disney's Beauty and the Beast, and moved to Broadway with it. He is heard on the Broadway cast album. He was also the mute King in the Broadway revival of Once Upon a Mattress. Mr. Lamberts spent much of the past decade in Pittsburgh, sharing his life with fiber artist Louise Silk and performing at the Pittsburgh Public Theatre, City Theatre, Pittsburgh Playhouse, as well as with the Pittsburgh Irish & Classical Theatre. In summer 2004, he appeared in PICT productions of Travesties and Uncle Vanya (the Brian Friel version). His final performance was in a two-man clown show E-lectricity at the Pittsburgh Playhouse in December 2004, according to colleagues.
At Pittsburgh Playhouse, he appeared in Quills, for which he was named 2000 Performer of the Year by the Post-Gazette; and the title role in La Bete. At Pittsburgh Public Theater, he played Sir Watkyn Basset in By Jeeves, but was too ill to appear in the subsequent Broadway run. He also appeared in PPT's A Midsummer Night's Dream in 1998.
In a rich career, the Toronto native (whose birth name was reported to be James Langcaster) played in theatres across Canada and the U.S. He was most widely known in Canada for his performances at the Shaw Festival under artistic director Christopher Newton , where he starred in A Flea in Her Ear, One for the Pot and Tons of Money.
Roles of his lifetime include Peer Gynt, Shelly Levine, Bottom the Weaver, Pseudolus, Chandebise/Posh, M. Jourdain, Trofimov, Player King/Gravedigger, Dauphin, Rev. John Hale, and Tartuffe, among others.
Mr. Lamberts was also a veteran of Ontario's Stratford Festival. He also toured in a one-man comic show called Gunga Heath.