First of all, the link is missing from your post.

Secondly. go to the History Channel website and see if the show is still listed on the line-up.

And finally, if the show is no longer listed, email them and ask why the show was canceled.

They'll say things like the ratings were too low, contract expired, etc.

It could have been just a short series, with no attempt to keep it going. Or a pre-set mini series, or a multi-show documentary.

It hasn't been canceled, nor has it disappeared. It's a prime time, late fall to early spring show. Season 1 of it is over, and season 2 will start up again when all the shows start up for the new television season, so never fear!