Little known
fact: The
Death Star in
Return of the Jedi is in fact the Death
Star III,
not Death Star II.
George Lucas himself named it the Death Star III - why, who knows? Why did he start at
episode IV?
The Death Star II appears in a few
Star Wars books. At a time between
The Empire Strikes Back and Return of the Jedi, the Empire begins
construction of the Death Star II, but the
Rebels get word of it and
destroy it in its very early stages, well before it was
operational.