This game plays a significant role in the 2007 Mike Bender film Reign Over Me. In the film, Charlie Fineman plays the game to cope with the death of his family in the 9/11 attacks, as the imagery of each Colossus falling to the ground was considered reminiscent to the collapse of the World Trade Center. With the approval of Fumito Ueda, the game was included in the movie.
It is not said in the game, but Team Ico has stated that the main character's name is Wander and the woman that he attempts to resurrect is named Mono.
If Wander walks up to the side of Agro, and the player presses the circle button, Wander will gently pat his horse.
The game was originally intended to be a sequel to Fumito Ueda's previous game, Ico (2001); early in development, it was known under the title "Nico" ("ni", Japanese for "two", plus "Ico").