Wander (1974)

Wander is text adventure written by Peter Langston in 1974. It is one of the earliest text adventure video games in existence, predating Colossal Cave Adventure. The game was originally coded in BASIC on a mainframe computer with multiple databases to create the worlds that formed the game.
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In the story included with the game, the player takes the role as a First Under-secretary to the Ambassador for an organisation called Corps Diplomatique Terrestrienne (CDT). Sent by Mr. Magnan to the mysterious country Aldebaran III, the player's mission to prevent up uprising against Terran nationals in a limited time.

- from Wikipedia