rail network, and workforce, the right candy making ingredients were in place.

But there was still something missing.

Confectioners needed to get their products out to the world, and as luck would have it, the world was about to come to Chicago.

(lively music) - So in 1893, you want entertainment, you are going to the Columbian Exposition because that's where it's at.

- [Narrator] The World's Fair was a celebration of cultures from across the globe.

It was a place to showcase the latest achievements and technologies, including one device that would take chocolate in a new sweet direction.

- In the history of inventions, mankind invented the submarine, the photograph camera, and the machine gun before anyone figured out how to mix milk and chocolate to create milk chocolate.

- [Narrator] Enter German engineer, J.M Lehmann.

His machinery for processing bitter dark chocolate into sweet milk chocolate, amazed scores of fairgoers, including one caramel maker from Lancaster, Pennsylvania, Milton Hershey.

- At the World's Fair, everything changed because that aroma with that deep, delicious chocolate odor, imagine if you'd never smelled that before, and he never had, because it didn't exist.

And he walks into this booth and he is wowed.

He immediately recognized chocolate was the future.

- [Narrator] Milton Hershey was so captivated that he offered to buy Lehmann's machinery on the spot and had it shipped to Pennsylvania.

- I don't want to say it was called nowhere, Pennsylvania at that time, but it was not yet called Hershey, Pennsylvania.

He took the chocolate making equipment back and started dipping his caramels in chocolate.

- But it's not just the machinery, it's also the introduction of new candies at the World's Fair.

And this idea of branded confections.

- [Narrator] Immigrant brothers, Frederick and Louis Rueckheim sold their version of caramel covered popcorn and peanuts, which they called Cracker Jack.

And Chicago socialite and hotelier, Bertha Palmer enticed fairgoers with a debut of the brownie.

- [Beth] At that fair, it was like candy went from black and white to color.

- People were now getting a sweet tooth, or in some cases more than one tooth.

So by getting a taste for these treats at the fair, this primed the path for even bigger business.