Most of facts are just memorization, whether mentally or through muscle memory. How to spell, how to write, how to type, definitions of words, etc. Why is it important to know who was in World War II? It's just random memorization, all I need to know is Nazi, Germany, and Hitler right? Why do I need to know who our presidents were? Eh, as long as I know is Washington, Lincoln, and whoever our current president is and I should be good, right?
It's important to know so when you live in your own country and someone says, "I'm from Delaware", you don't question whether or not that is a state or a city. It's important to know so when someone says, "I'm from New York", you don't only think of Manhattan. When someone says, "You know, all these current political issues are just reminiscent of what John Adams went through", you don't think "John Adams? Isn't that a beer company?".
Knowing this shit doesn't make you intelligent, it just makes you not an idiot who only memorizes Pokemon and Star Wars trivia.