Why wasn't Russell Brand allowed in Canada?

[Tresbn00]

I have read several accounts but have been unable to determine why Canada wouldn't allow him in the country.  One article alludes to Japan not allowing him in Japan because of his Drug convictions.  Maybe it is because his wife's, Katy Perry, music is so atrocious...lol Has anyone bought any of his books?  I heard that he was a wild thing...drugs sex and rock and roll at levels that would make addicts in each of the respective areas shudder at achieving!