Alcibiades was the biggest jerk to ever live in the Classical Age. Born near Athens, Greece, Alcibiades earned a reputation growing up as one of the most attractive men ever in history. I mean, you know that when the local histories from your era make extra-special sure that they mention how hot you are there's got to be something to it. As a result, naturally, Alcibiades was getting laid more than Wilt Chamberlain in a New Jersey bordello. Chicks (and dudes) pretty much threw themselves at him every time he walked out the front door of his super-fly bachelor swinger's pad, and he even hooked up with the legendary Greek philosopher Socrates; an achievement that even the most archconservative gay-bashing bible thumper has to concede is pretty damn impressive. Before Socrates swigged that shot of hemlock, he actually wrote a couple works about how freaking hot Alcibiades was, calling him pretty much the most attractive man ever to live in all of history. Alcibiades made sure to dress the part of an eccentric millionaire superstar as well: His golden shield was studded with diamonds and jewels, and was pretty much the Ancient Greek equivalent of Lil Jon's Pimp Chalice. He was pimpin' before it was pimpin'.
Alcibiades was pretty handy in battle, proving himself so well at the Battle of Delium in 424 BCE that the Athenian Commander give his daughter to Alcibiades in marriage. Alcibiades lived with her until she died from cancer or something and then he continued to go about his wild ways of hooking it up with Republic courtesans and such.
When the Peloponnesian War broke out between Athens and Sparta Alcibiades was appointed commander of the Athenian Naval Forces. He was so pumped up about being in charge of this campaign that the night before he was going to ship out he got totally wasted and ran around downtown Athens screaming and pulling the schlongs off of every statue in the town square. When the Athenian government woke up the next morning and found a pantheon of dong-less gods lining the streets, they issued an arrest warrant for Alcibiades and stripped him of his command.
Alcibiades didn't give a crap though. He ditched the Athenian Army and went over to Sparta, where he helped the Spartan king fortify the town of Decelea since he knew there would be an Athenian attack there. The King of Sparta did this and the Spartans won a tremendous victory over the Athenians. Alcibiades was livin' large until the King found out that his daughter had been impregnated out of wedlock by his newest General. Oops.
The Spartan King flipped out and Alcibiades had the good sense to get the piss out of Dodge before he had his balls chopped off, so he fled to Persia. Alcibiades lived in Persia for a while and befriended the Sultan, but eventually defected back to Athens where he was received as a hero. He fought with the Athenians as a lesser military officer until their final defeat at Aegospotami in 405 BCE, when he then fled back to Persia.
Alcibiades tried to rally the Persians to attack the Spartans, but by this point everyone had put up with enough of his crap. A bunch of Spartans convinced the Persian Sultan that Alcibiades would hump his daughter when he wasn't looking (which he would have), so Artaxerxes sent a bunch of Persian warriors to attack Alcibiades while he was in the shower. They set his house on fire while he was bathing, but he didn't even give a crap. He grabbed his dagger and ran outside buck naked trying to stab anyone that came near him. Eventually he was killed after he got nailed by fifteen arrows.
Alcibiades was a badass because he was such a total douchebag to everyone that supported him. He was a fierce warrior and also one of the most attractive men of his era... not something that can be said about a whole lot of people. He played the political games perfectly, led his forces to military victory and spent the better part of his life getting busy with anyone that would let him. In the end, that's pretty badass.