SILVER AGE BATMAN

The transition from Golden Age to Siver Age (later designated Earth-2 and Earth-1) versions was unintentional, and had no clear splitting point. Batman's early history was much more consistant between versions than Superman's, but in some cases, character traits and continuity events that would later be ascribed specifically to different versions of Batman had actually been associated with a single Batman in a past story. Once the Earth 2 & 1 concept had been developed, the Earth-2 Batman was linked with the original appearance date while the Earth-1 Batman was kept static by floating his past history. So, whenever the Earth-1 continuity comic book was published, Batman was born about 30-35 years before, and commenced his career at in his early 20s. Later Earth-1 stories had to let Batman be closer to the 35 mark to allow for the past histories of his Robins.

55555 Bruce Wayne was the son of wealthy parents, and might've grown up to be one of the "idle rich" had it not been for a life shattering tragedy when he was a small boy. Bruce was taking a walk with his parents in Gotham City to stretch their legs after seeing a Zorro movie when they were confronted by a mugger (called Joe Chill) who murdered Bruce's parents right before his eyes. The shock, anquish, and outrage at the experience boiled in the boy until the day of his parents' funeral, when he solemnly vowed revenge against all criminals.
55555 For many years Bruce trained his mind and body for the task in secret while letting the world think he was a soft aristocrat. When he finally felt that he was ready to make good on his vow, he sat in what had been his father's study trying to figure out exactly how to go about it. "Criminals are a cowardly, superstitious lot" he thought. How could he use that against them? Just then a bat fluttered through the window. That was it! "I shall become a bat!" he resolved.
55555 Dressed in a bat-motif costume and armed with amazing tools and non-lethal weapons, Bruce began his crime fighting career in earnest. At first he operated outside the law. But, since Batman never crossed the line into killing or judge/jury/executioner vigilante behavior, he soon found an ally in Commissioner James Gordon.
55555 Dick Grayson (Robin) joined Batman early in his career, and the two became a legendary team. Later, Commissioner Gordon's daughter Barbara would be inspired to adopt the costumed identity of Batgirl, and would sometimes team with Batman and Robin.
55555 When Dick went off to college, Bruce decided it was time to update and streamline his life. He closed up Wayne Mannor and the Batcave headquarters beneath it and moved to the top floor of the Wayne building in town with Alfred Pennyworth, his trusted major domo and assistant. An abandoned subway station beneath the building would serve as a scaled-down Batcave. Bruce would become more involved in using Wayne enterprises to improve the urban situation on the larger scale, while relying more on his wits and ingenuity to fight crime as Batman.
55555 After Dick Grayson stopped assisting Batman altogether (he'd moved on to other things), Bruce took in another young boy with a circus upbringing whose parents had been killed by the criminal known as Killer Croc. This boy, Jason Todd, would assume the role of Robin.
55555 Although cosmic-level adventures weren't really up his alley, Batman was active in the Crisis on Infinite Earths.
55555 The Earth-1 continuity ended with the Crisis in 1985. In the hypothetical future of Earth-1, a sort of anti-superhero mania would spread across the Earth in the late 1980s, which would drive almost all costumed heroes into retirement, or away from the Earth entirely by the end of the decade. During this period, great civil unrest would prompt Batman to rebuild the Batmobile into a massive tank, which he used to put down riots. This era left the Batman's greatest foes vegitating in hospitals, presumably from confrontations with Batman. Around 1990, Robin (Jason Todd, around 20 at the time) would die in action, prompting Bruce Wayne to hang up his cowel.
55555 For a decade Bruce would resist the almost overwhelming urge to become Batman. He drank. Participated in dangerous racing events. His relationship with Dick crumbled. His relationship with Selena Kyle (the reformed Catwoman) was loving, but never developed into marriage. Bruce Wayne was an empty shell.
55555 Meanwhile, a culture deprived of heroes and (more importantly) the heroic ideals they represented, degenerated. A savage street gang called the Mutants threatened to raze Gotham. The idiot politicians of the world were edging the planet towards destruction. And noone stood for what was right.
55555 Finally Bruce snapped. The Batman returned with a vengence. Joined by a self-made Robin (Carrie Kelly), the 55 year old Dark Knight managed to turn the Mutants into an army for order and civilization just as a limited nuclear strike threatened to sink Gotham into hopeless chaos. Along the way he also managed to defeat his greatest old enemies in climactic confrontations.
55555 Batman had preserved order in Gotham and stood as a beacon of the heroic ideal while the rest of the Nation was in riots and chaos. The small-spirited "leaders" of the country couldn't stand to be shown-up so badly, so Superman was dispatched to put an end to Batman's illegally overt heroism.
55555 Superman underestimated Batman, who'd been preparing for this conflict for years. After beating the daylights out of Superman, Batman spared his life, sat down, and died of a heart attack.
55555 Or so it seemed. Bruce had previously transferred all his wealth secretly to hidden accounts, and had the Batcave and Wayne Mannor blown up at the moment of his "death". After the funeral, Bruce's body was secretly removed from the grave just as the drug which created the appearance of death wore off. Bruce (no longer in costume) would lead Robin and the former Mutants into the distant reaches of the endless, natural Batcave where he would train them to be an army of heroes to serve a world that desperately needs them.