Chien Wen Kung points to the original 1977 New York Times review of Star Wars:

In opposition to these good guys are the imperial forces led by someone called the Grand Moff Tarkin (Peter Cushing) and his executive assistant, Lord Darth Vader (David Prowse), a former student of Ben Kenobi who elected to leave heaven sometime before to join the evil ones.

Ah yes, the old "executive assistant" trick. Reminds me of the summer I worked as a hotel clerk and put it down on my resume as "reservation manager" or something of the sort. Shameless, yes, but it's what you have to do. Anyway, the full review's worth a read; apparently there were oblique Wizard of Oz references in Star Wars. Very cool! But, um, what were they? A prize and a pony ride to whoever can think of even one.