As a historical note, the first comic book I ever bought was a Batman comic. In it, he battled the KGBeast who was upset about Earth Day supplanting Lenin's birthday as April 22nd's claim to fame. Oh, and he wanted to assassinate Reagan. But I really think it was the Lenin's birthday thing that drove him. It's a good thing Bats locked him away in a sewer, though, as the Beast would have no doubt moved on to other people born on the 22nd, thus depriving the world of David Luiz's marvelous hair.
Anyhoo, the Batman. Like Superman, Batman is one of the core characters to the DC universe. It's that whole idea that the role and abilities of Batman are actually obtainable to the average reader. He's not an alien fueled by the yellow sun, he's not a magical being blessed by the gods, he's just a guy in a cape with several billion dollars worth of toys and one really bad day. I admit I would have squandered Batman's upbringing were I in his shoes, become a creature closer to Billy Madison than the Dark Knight.
So let's keep out Batman on track, shall we? Parents gunned down in an alley, Joe Chill, pearls. Young Bruce Wayne grows up an orphan with only his family butler Alfred and dog Ace for company. He's an angry kid, gets into fights at boarding school, and arrogant to boot. By the time he's 16, he's done with school and school's done with him, but hey, that's fine, because it's around then that he gets the crap scared out of him by a bunch of bats flying in through a window. Thus the idea of the Batman striking fear into criminals and his world-hopping sojurn of training begins. He'll travel, learn, then return to Gotham to test out what he learned on the local criminal element. If he find he's missing something, he goes out again for more training.
To me, this is an important part of why Batman does what he does. He's constantly testing himself. It's not just vengeance or anger or whatever, but a constant need to improve. If his parents had not of died, he'd have become a surgeon, a mogul, an Olympian, a physicist, and possibly all the above. Their deaths gave him a direction for his energy. Without that focus, he would have been adrift, moving between field after field until eventually he had a mental breakdown. Gee, I wonder if there are any other characters in the DC universe who are amazingly good at what they do, but also mercurial and more than a little bit mad?
So going by Superman's timeline, let's say that Batman was actually active in a fully recognizable Bat-form roughly two years before Superman's picture hit the front pages. Although, Batman is a bit older than Superman, but he's still within the same age range. Like Superman's adventures with the Legion as Superboy, Batman had some younger adventures during his walk-the-earth, trial-and-error period, but they're not important right now. Batman arrives on the world stage maybe a month after Superman, his picture taken by reporter Vicki Vale. "Gotham Has Its Own Caped Crusader" the headline reads.
The arrival of two guys in tights and capes fighting gangsters starts to bring the wackier criminals out of the woodwork. Poor Gotham gets the brunt of the costumed whack-jobs as you need to have actual superpowers to make a go at crime in Metropolis. But they are also drawn to the Batman for some reason. In one of his many court-ordered therapy session at Arkham, Jervis Tetch supposes he came to Gotham because at heart he is a fearful person. To conquer that fear, he had to conquer the Bat. Batman scares the crap out of the ordinary criminals, so only the extra-ordinary remain.
Speaking of Batman's villains, it is a rule in the Drewniverse that all Batman badguys must be a foil or twisted reflection of some part of Bruce's identity. I think this is the rule at DC as well, but who knows. Still, that'll be fun to get into when we start to reboot the villains.
So as we come to Issue #1, Batman is still maintaining his dual life as Bruce Wayne, millionaire playboy. WayneTech, formerly known as Wayne Industries, is a twisting octopus of a company, holding many subsidiaries with diverse interests such as military, space flight, food production, transportation, and so on. CEO Lucius Fox has kept the company growing for years. Maybe WayneTech is not growing as fast as LexCorp, but investors generally consider the Gotham-based company a safer investment. Bruce Wayne is a majority shareholder in the company, although outside of random visits, he usually lets things run without seeming to meddle.
At the start of Issue #1, Batman is about to be without a sidekick. Dick Grayson took up the mantle of Robin just over 1/2 a SU ago and the tights are starting to wear thin. He feels that he's learned all he can in Gotham and is chomping at the bit to go out into the world like Bruce did when he was that age. Barbara Gordon has already given up her mantle as Batgirl at the request of her police commissioner father. Something Happened, you see.
The Batcave is beneath Wayne Manor and it's chock full of tools, toys, and trophies. When not prowling the streets of Gotham, Batman spends most of his time down there working and training. He would prefer to be alone, true, but he has learned over the years that if he really wants to improve himself, he needs help. Thus the sidekicks ("Sometimes you learn more by teaching others how than just doing it yourself.") and team-ups ("Chance to see a nigh-legendary warrior woman fighting style in action? Please.").
I don't like 100% grimdark Batman, but we're not going for Adam West here either. Jamie Hyneman dry humor, perhaps.
And on that mental image of a walrus-like mustache drooping from beneath the cowl, I leave you. Again, a pretty standard origin for Batman with the real fun coming in the villains, the stories, and the thing I'm looking forward to the most, who will be the next Robin?