"Sometimes things that are not true are included in Wikipedia. While at first glance that may appear like a very great problem for Wikipedia, in reality is it not. In fact, it's a good thing." - Wikipedia.
It's not a documentary, actually, but rather what James H's link describes as a 'dramedy'. The BBC web site prefers the term 'history drama'. I just hope it's not an example of that execrable species, the docudrama.