This anime alternates between being genuinely funny and really really annoying. Much of the humor comes from randomness, which is a hit or miss (Italy's "Pastaaa!" moment, coming after some actually interesting things other characters said is a definite miss, while summoning the Devil and having Russia appear, or Austria's "He was there THE WHOLE TIME!!" actually made me laugh). When it deals with actual history and not bland Ho Yay or crazy, unmemorable antics from various characters who you really can't care about, the series is not bad at all. Arcs that actually give some characters and their relationships more meaning are a true redeeming quality for the rest of the series. If you can see past these flaws you will probably enjoy this series, and while I did not like it I think it is worth a read.
You notice I said read. Well, that's because I wouldn't watch the anime, and would go with the web comic or manga. Apart from the really annoying closing, the animation is frankly rather appalling. It abuses sock footage and panning of still frames to a rediculous degree.