Regardless of the world, in each universe in parallel plains of existence, young lads named Bruce Wayne faced immeasurable tragedies. On Earth-One, this led to the boy becoming the Batman, as had decades earlier been the case on Earth-Two with its own Bruce... when both youngsters found themselves instant orphans due to the selfish actions of common crooks. Training for years to come, they would don the disguise of the Darknight Detectives. On Earth-Three the lad became the evil Owlman instead, and on Earth-Five he was a witness to an older Batman saving his parents, inspiring him to heroic heights. In each instant, legends unmatched were born.
In the civilian lives of the Batmen, however, their histories diverged somewhat. Particularly on the first two parallel planets, the name Bruce Wayne was at first synonymous with wealthy playboys without a (seeming) care in the world. Under such masks, of course, were the more determines Dark Knights. Still, it eventually became necessary for the Waynes to graduate to a more mature social standing given their innner convictions. On Earth-One, Bruce became the CEO of the Wayne Foundation which had several business and philanthropic activities. on Earth-Two, Bruce chose a more public service, elected to the rank of Police Commissioner of Gotham City.
While CEO Wayne used his corporate mechanism to achieve social change with the ultimate goal of supporting his costumed crusader, Commissioner Wayne forsook his own caped crusade upon losing his dear wife Selina and thus diverted all his heroic energy into his public office instead. Eventually, it was an attachment with the head of the Foundation... Lucius Fox... that caused CEO Wayne as Batman to revoke his membership with the Justice League, since they refused to assist him in saving his old friend. And it was the wayward conduct of the Justice Society, coupled with the malipulations of Psycho-Pirate upon both Wayne and his former comrades, that caused the Commissioner to seek out a vendetta against the Society. In the end, however, peace was restored between the Batmen and their bosom buddies. And their legends were furthermore solidified.