Board Thread:Questions and Answers/@comment-4549272-20140628163739/@comment-112155-20140628174714

As Star-Lord was a kid in the 80s, it's safe to asume that it is set during present time.

Also, the post-credits scene of Thor: The Dark World and the Guardians of the Galaxy Prequel Infinite Comic would help us to place the events from the movie in the timeline.