Honestly.. Yes.
He's without a doubt in the top 5.
again, I'm saying influential. That doesn't mean good.
Look at what he was able to do. He had little education and little resources in the beginning and he was able to overtake Germany, flip their depression giving 5-6 million people jobs. Taking their research and military leaps and bounds ahead of it's time. In the early days of his reign, he was loved by his country. It's takes an influential person to do this.
It's kinda funny how most fictional villains always want to "rule the world". Hitler came as close as anybody in the modern world and nobody will ever even get as close as he did. This dude controlled a large part of Europe and Africa and if you count his alliance, he had even more.
Of course he was crazy and a horrible person, especially during the final years of the war. Who knows if he would have laid back on the drugs, and listened to his Generals more.. he could have accomplished more.
With all that being said... he's the worst person of the last 100 years and shouldn't be glorified at all, however he's a very important part of history whether we like it or not.
Like Eddie said, we don't have to take everything so damn serious. Especially shit that happened before we were even born. Just my 2 cents