Cultures are a core component of The Lord of the Rings TCG. A culture's function is to easily distinguish cards that are likely to be related to one another (usually by a thematic element, such as race or locale). There are plenty of cross-culture strategies to be had, but for the most part cards of one culture play best with other cards of that culture. Each culture naturally has its own strengths and vulnerabilities; for instance, the Elven culture excels during the Archery Phase, but the Shire culture – having no access to bows or bowmen – struggles in that phase but makes up for this in other areas.

Excluding sites and The One Ring, every card in the game belongs to one of sixteen distinct cultures. It should be noted that the Gollum culture is unique in being the only cross-alignment culture–that is, having both Free Peoples and Shadow cards, in line with both sides of Smeagol/Gollum's split personality. All other cultures are either all Free Peoples or all Shadow.

Following the release of Shadows, the Shadow-side cultures were rearranged from the more realistic faction-dependent orientation (Isengard, Moria, Dunland, etc) to a race-oriented one (Man, Orc, and Uruk-hai).

When the game's first set, Fellowship of the Ring, released in 2001, it brought with it the first nine cultures: Dwarven, Elven, Gandalf, Gondor, Isengard, Moria, Ringwraith, Sauron, and Shire. No new cultures were introduced until a year later with the additions of the Dunland, Raider, and Rohan cultures in the second base set, The Two Towers.

The Gollum Culture was the only culture to make its first appearance outside of a base set, due to timing with the release of the movie The Two Towers. As part of Decipher's licensing agreement, they were not permitted to reveal any so-called “spoilers” (in spite of the books the movies were based on having been publicly available for nearly fifty years), and as the Two Towers set was released a month in advance of its namesake, the developers needed to wait for the Battle of Helm's Deep expansion four months later to explore Gollum's schizophrenia. Interestingly, it is the sole culture to feature both Free Peoples and Shadow cards. It would be the last new culture of the Movie years, and the last major culture to be released.

After the release of the Mount Doom set, Decipher reconsolidated the various Shadow cultures and created three new ones in an attempt to keep the card pool fresh. These cultures were Men, Orc, and Uruk (not to mention the renaming of Ringwraith to simply Wraith). This move in general was unliked by the player base, some viewing it as a marketing move to force players to yet again purchase more cards or be doomed to obsolesce. Unlike the previous incarnations, these new cultures could draw, from their first appearance, upon images and material from all three films. Following the Shadows release, no further cultures were brought into the game.

Shortly after the release of The Two Towers base set, it was revealed that Decipher's initial intention was to introduce Dunland and Raider as a single culture, named Evil Men. Ultimately this plan was discarded, since doing so would have restricted a player's choice of Shadow cultures to two in the set (Isengard being the second).

Speculation was rampant after The Two Towers as to how the Ents would be incorporated into the game. Rumors predicted an Ent culture in the works for Battle of Helm's Deep. As it turned out, Ents were instead incorporated into the Gandalf culture.