In the end scene of Return of the Jedi, the previous actor (Sebastian Shaw) who played Anakin Skywalker (Darth Vader) was replaced by Hayden Christensen.
When did George Lucas make this change? Was it prior to the Bluray release of the Saga?
It was prior to the release of of the blu-rays. According to this, in 2004 a new version of the Special Editions was released on DVD and this change was included.
From the link:
In 2004, in addition to an extensive and comprehensive hi-definition digital cleanup and restoration job by Lowry Digital, the original trilogy films were changed once again for their release on DVD. In these new versions of the films, a few changes which had been made for the 1997 Special Editions were removed. Even more changes were made to the films, however.
Another notable and quite controversial change was to a scene at the end of Episode VI, when the spirits of Obi-Wan Kenobi, Yoda and Anakin Skywalker look upon the Rebels' celebration. The original actor who played Anakin in this scene (Sebastian Shaw) was replaced by Hayden Christensen, the actor who played Anakin in Episodes II and III.
There was no "young Anakin" when the Return of the Jedi was made, so putting an actor in there other than Sebastian Shaw would make no sense. Put a young Anakin that no one has seen, and everyone would be wondering "who in the heck is that?"
Since the ending scene depicts Anakin Skywalker (saved, no longer Sith), not Darth Vader, it would make sense that the physical manifestation would be of the Jedi version of that individual's life. The Sebastian Shaw was the Darth Vader version.
If spirits get to choose, I would think the choice would be from happier, healthier days, vs maimed and using a war suit for life support, as well.
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