Baseball had first taken root on this continent in the mid 1700's when English lads brought an offshoot of the game of cricket to our shores. This game, where the fielders put out a runner by belting him with the ball as he ran from base to base, was called Rounders.
There were many variations of Rounders as the game had no "official" rules. It was usually played according to local custom, meaning the number of players on a side, the number of bases (usually anywhere from two to five), the way they were laid out, the distance between them and other rules would vary from place to place. It was basically a pickup game that was played by children.
In 1845, in New York City, the 25 year old Alexander Cartwright took various elements that were used in these different forms of early baseball and, adding a few wrinkles of his own, fused them into regulations that stand today.
Abner Doubleday was not interested at that time. Or so it is said. Anyway, he was not a part of Baseball.