Lord Of The Rings: Tactics was one of the very early PSP releases, at a time when the system had very little in the way of turn-based strategy or even fantasy-themed games. I think they were pretty much counting on that and the license alone to carry sales, as it's otherwise a pretty mediocre and unambitious effort.
The one intriguing twist here is that you can play as either the Fellowship or the Host of Mordor ... well, it's initially intriguing, but once you actually play as Mordor you'll be disappointed. More on that later in its own special paragraph. Whichever side you choose, you go through a linear series of about a dozen maps that cover the major battles of the films.
You're only playing very small segments of these battles, however. You have six "main" characters that you can upgrade in between maps, and then you get some other characters on a per-map basis that have fixed levels and abilities. For the Fellowship, your main guys are Sam, Frodo, Gandalf, Aragorn, Legolas and Gimli. Some other major characters like Boromir and Arwin appear here and there, and some maps give you a few Rohan or Gondor randoms in support too. Battles generally range from about 3 to 10 characters per side.
There's a haphazard feel to how everything is put together. The story advances with nothing more than clipped-out movie scenes between maps, and the battles have kind of a weird and contrived feel. Series purists will definitely go nuts right off the bat at Sam and Frodo killing Lv.1 Ringwraiths at Weathertop by hucking rocks at them. Characters are also sometimes just randomly missing or added for the sake of play balance too.
Fortunately, the gameplay is at least basically decent with no major hinks or control problems. It's as basic as it gets -- move, melee attack, range attack, spells for Gandalf, healing items -- but maps are at least decently laid out. Each of your six major characters earns EXP for each completed map, even if they aren't present. You also earn money based on your performance (number of turns and keeping characters alive), and can use that to purchase either items or new skills for your characters. You're allowed to repeatedly play older maps to grind for money, and for EXP up to a point (there's a level cap where you stop getting experience for each map).
If you thought the Fellowship had silly contrivances, though, wait until you fire up the Mordor maps. Instead of creating custom maps that would actually make sense in the LotR universe, they basically just did Mirror Mode of the existing Fellowship maps. In the first map, Weathertop, the objective is to deal 50 points of damage to Aragorn ... surrounding and murdering Sam and Frodo is entirely possible, and really should win you the entire campaign right there, but it doesn't count for anything other than bonus gold if you do it. And in Moria, the Hobbits are inexplicably all missing, replaced by ... Boromir and some Gondor randoms? The devs clearly either had zero clue how to implement Mordor or were just given zero time by EA to do it in a sensible way, so they just threw together assets in a totally haphazard way just to have "Play As Mordor!" in the game's advertising.
They came up with a decent (if very basic) turn-based engine, but everything else about the game absolutely screams "rushjob to be a launch title". You aren't missing anything if you skip it other than some laughs at things like playing as Sauron, Grima trucking Aragorn in 1-v-1 combat or the Hobbits bullying the poor Ringwraith King with thrown rocks.