There are 200 different alien species in this movie. Writer, producer, and director Luc Besson wrote a 600-page book describing in detail all the species. The actors had to read that book prior to filming so they could adjust their performances depending upon the species with whom they were interacting.
The Welcoming Captains were directors and/or writers with whom writer, producer, and director Luc Besson has worked.
Writer, producer, and director Luc Besson waived his own salary in order to get this movie made, which was a life-long passion project of his.
The first two trailers for the film used the song "Because" by The Beatles. This was the first time a movie director was able to obtain the rights to use a Beatles song in a film advertisement. Permission was granted by Sir Paul McCartney.
With a final production budget of $180 million, this film was officially the most expensive ever made in France at the time of its release. It significantly exceeded the budget of the previous record holder, Luc Besson's The Fifth Element (1997), which had a production budget of around $90 million and was the most expensive French movie at that time. If adjusted for inflation, this film is still more expensive than Besson's earlier picture.