Sengoku Musou

Same historical era, Sengoku (Warring States) Era, of Japan. In Gifuu Doudou, story revolves arounds Kanetsugu and Keiji, friends of two brothers of Sanada clan: Yukimura & Nobuyuki. 

Both anime take place in Japan's past and revolve around samurai. Furthermore, both have slight additions of fantasy elements to their otherwise quite accurate depiction of major past events.  

these Anime's know the way of the samurai. if you love historical anime with ninjas and samurai warriors then this is for you. the fighting skills and spirit of the warriors within these anime's are very similar and unique; the only difference being sengoku musou does not have a supernatural element to it like donten ni waru.  

These are both over the top historical fictions based around samurai. Sengoku Musou is not nearly as wild, but it is based on the same time period even sharing several characters between the series. 

Both shows tend to go quite deep in the politics and war with quite lengthy explaining of the strategy used. Main difference is that Madan no Ou to Vanadis is harem/fantasy action, while Sengoku Musou is a historical fantasy action. On the bad side - both shows have quite mediocre animation and visuals, with characters going off-model pretty often. Sengoku Musou is a little better on this direction, though (no weird dancing from the soldiers has been spotted and there's less slide-shows).