When Truman dropped the bombs, he had the entire world's attention. I doubt that any single leader or country at that time would have even thought about challenging the US for the remainder of his presidency. I don't know that anybody has ever enjoyed that much influence. He would be most powerful by default. Not because he was the most powerful character, but he was in power at the end of WWII.

Johnny Manziel

Yeah, but more powerful than Johnny Football? That’s a tough one.

That's fair. I could get on board with that. Agree it didn't have anything to do with him as a person, just the circumstances. Anyone in that role at that time would be the defacto winner. It might never occur again in human history. Except for whoever gets AI first. Could happen again then.

Since we can't use the most powerful "human" to ever live, " מָשִׁיחַ " The Mah-shee'-akh...

The next most powerful human to ever live is about to be revealed, he will make everyone listed seem like a schoolyard bully !!!! you will know his name, I won't... you can call him Uncle Abomination of desolation...

If you want someone who won every battle Alexander the Great
If you want t most powerful no one but Samson killed three thousand with a jawbone
After that will be Antichrist or Satan

You two should get a room.

Why, are they not allowed an opinion? It's a flawed poll.

It doesn’t really matter to me. The most powerful human either is or will be dead just like the rest of us less powerful humans one day. How much power or wealth you may have had on earth won’t matter when you’re dead.

Just spreading love and laughter.

You best repent bub. Your high vis and humor will not save you when the King of Kings returns.

He didn’t go anywhere as he is in my heart.

Teddy Roosevelt.
https://www.britannica.com/summary/Theodore-Roosevelts-Achievements

This is an underappreciated response. I voted Khan, but can appreciate the logic for Truman.

Poll is missing the versions of Terminators. oh wait Cyborgs.

Conan then.