When History Channel started they were mostly WWI and WWII documentaries, and they weren't "storytelling" ones, just cold hard timeline descriptions of movements and battle tactics.
They had one about the naval battles on the Pacific, pretty slow and boring but had tons of direct information about how both operated, not being shy of saying the americans were just as brutal as the japanese by firebombing and burning entire islands even if they had civilians in it.
At night the Eastern Front ones were shown, mostly dealing on why Germany became an aggressor but showing context from WWI and before, so not your usual "mustache man bad" but actual socio-economic justifications.
As you can expect, that kind of format lasted one year or a bit more at most, later on it went Hitler UFOs and reality shows, but sometimes stuff like car shows, that ancient buildings show presented by Robocop, thematic investigations and so on appeared, those were really good but nobody watched them.
We are talking 2003-2005.