Latin, though dead, is an incredibly valuable language to know. I'm admittedly biased on the topic, having studied the official language of the Holy See for six years now, but my personal affinities in no way change the undeniable benefits of studying the language of the Ancient Romans. Studying Latin will do more than just making a lot of the spells in Harry Potter easier to understand. Here are some pretty cool things that happen when you study Latin.
1. Your vocabulary expands.
Approximately 29% of English words are derived from Latin, meaning that you learn not only a bunch of really interesting etymologies but a whole lot of words that you otherwise might not have stumbled upon. Like defenestrate. It's a good one. Look it up.
2. Your grammar goes from mediocre to on point.
This is true about studying any language really, but the uniqueness of Latin grammar will stretch your brain in ways you didn't even realize it could. Ever heard of a passive periphrastic? How about a future less vivid? After studying Latin for a couple years, you'll be throwing participial phrases around (and identifying them) like nobody's business.
3. Picking up Romance languages becomes a little easier.
Latin is the mother of the Romance languages, so languages like Spanish, Portuguese, and Italian originated from it. That means that with a solid Latin background, a lot of the vocabulary will sound familiar and be a lot easier to remember. That being said, if your goal is to learn Spanish, just learn Spanish. Learning Latin first is a pretty round about a way of doing that.
4. Your writing improves.
Since we've already established that studying Latin improves your vocabulary and grammar, this is kind of a no brainer. But just in case you're still unconvinced, look at J.K. Rowling. She studied Classics at university, and she's the genius behind Harry Potter. Sure, one wildly successful billionaire author doesn't make Classics a goldmine for high-paying jobs, but a Latin background might just give you the edge you didn't know you need.
5. You learn about the politics and culture of Ancient Rome.
...and how certain movies may or may not be the most accurate representations of it. But seriously, you learn a lot about Roman civilization by translating texts from it. Most Latin courses emphasize learning about the culture just as much as vocabulary and grammar, so you'll have a really interesting well of ancient cultural knowledge to draw from. For example: gladiators were the sex symbols of ancient Rome, and their fans would write graffiti that said things like, "Celadus the Thracian makes all the girls sigh."
6. You read some really important texts.
Sure, there are some really good translations of texts like Virgil's epic Aeneid, Cicero's brilliant orations, or Catullus's raunchy poems, but there's something magical about reading them in their original language. Latin may not be the most flowery or sentimental language, but its dignity and stoicism are definitely remarkable and admirable. The way these men wrote and the things they wrote about have undeniably influenced today's rhetoric and literature, and it's really amazing to read them firsthand.
7. You ensure that even though Latin may technically be dead, it lives on.
Latin may only be spoken in churches and on certain Finnish radio stations, but that doesn't mean it can't thrive in other settings. If the fact that it's already survived thousands of years of civilization growth and decline isn't a testimony to Latin's importance and relevance today, then maybe this is: archeologists are still finding new artifacts in this day and age, and those archeologists won't be around forever. We need people who can interpret fragments of texts and situate them in the times in which they existed, so we can continue to study and learn from the lives of those who came before us. Ancient history is interesting and important, and Latin is just one of the keys to it.