Milton Hershey was born in Derry Township in 1857 to his parents, Henry and Fannie. Milton dropped out of school after the 4th grade and at age 14, went to work. He worked at a job he HATED at a newspaper, then got a job with a candy maker.
After 4 years, he started his own taffy shop in Philly and it stayed open for 6 years. He then went to Denver and learned how to melt caramels.

After 10 years and a lot of failure, Hershey returned to Pennsylvania in 1886 (age 29) and borrowed money from his mom's family to open Lancaster Caramel Company (shown below). By 1894, his "Crystal A" caramels had made him a rich and respected man.
In 1893, Hershey became enamored with chocolate while at the Columbian Exposition in Chicago. There he bought some machinery to help him make chocolates.
The recipe he used back then is most like the Hershey's Special Dark bar we know and love today.
At first, chocolate was just used to cover caramel but it quickly came to the forefront as a star player. The earliest products were lots of chocolate treats in a variety of shapes and designs, everything from cigars to "Princess wafers". However, Hershey was still unable to perfect milk chocolate.
In 1900, after lots of determination and experimentation, the inexpensive (a nickel!), the Hershey Milk Chocolate Bar debuted and was insanely popular!
Hershey did a lot of his experimenting on the farm where he was born (now known as "the Homestead"). He had sold it in the 1860s to pay off debt, but bought it back in 1897!
Hershey then sold his Lancaster Caramel Company for $1 million so he could focus on manufacturing milk chocolate. The "Great American Chocolate Bar" was born.
At this point, Hershey needed to expand to meet demand, including a bigger factory, more equipment, more employees, and more milk!
After exploring around, Hershey moved his whole set-up in 1905 right back to Derry Township