[quote="TheLionPrince"]Seeking advice from
Lord of the Rings fans, is it customary to watch the original trilogy in order to understand the
Hobbit movies?[/quote]
Not necessarily. Most of us who are fans have already seen the original LOTR movies before any of the Hobbit films since they've been out 10-12 years previously. When it comes to basics, just know that the Hobbit (being split into 3 films) is the prequel to what would lead into Lord of the Rings, in which involves Bilbo Baggins and his adventure. In LOTR, a following, yet different adventure involves his nephew, Frodo Baggins. Bilbo does appear in LOTR as an older man since time has passed by, but he is not involved as much. Even though I didn't grow up with the original trilogy at the time since I was about 5-7 years old, I'm happy that I am part of the fandom and got around everything. I've been a fan for about 2 months, read the books (Hobbit > Fellowship of the Ring > Two Towers > Return of the King) and seen all the movies. In your case, you can watch the Hobbit films first, then the LOTR films, and you'll be just fine.
Of course, I saw Desolation of Smaug a few days ago and it was awesome like I thought it would be. I was happy to see Legolas again and still continue to be a bad***.

It was interesting to actually see how his character was different than in LOTR since this is before dwarves and elves made a compromise between each other and had their prejudice on one another. I will say this: When I saw Smaug on screen and heard his voice…My jaw dropped to the ground because he was so epic. OH MY GOSH WHAT A DRAGON HE IS!
