While Sydney Newman may have created Doctor Who, it was Verity Lambert who ran the show during the initial years. And of course it was Terry Nation who created The Daleks, and he was Welsh.
Still, Canadian doesn't count because it's still part of the Commonwealth. I'm curious about any American showrunners. Not to disparage, I'm just genuinely curious.
I know in the mid-90's when they were trying to revitalize the series with 8th Doctor Paul McGann, it was broadcast on FOX and even had Eric Roberts as The Master.