Who is the master of Dol Guldur?
Next, since necromancy is a major weapon of Sauron’s in these movies, the name “the Necromancer” must be used prominently. However, when Azog shows up resurrected, it’s a clue as to the nature of the evil presence in Dol Guldur. So this is the first time that Dol Guldur has been linked to the art of necromancy, and that tells us that its master is not already known as “the Necromancer” (whereas in the book, that’s his longstanding name). Since necromancy was a well-known specialty of Sauron’s going back to the First Age, that means that “the Necromancer” in the movie is instead merely an old name for Sauron—one that’s being revived now as particularly appropriate.
So, at the time our story begins, the Wise know of the existence of a malign presence in Dol Guldur. Not only do they have no suspicion that it is Sauron returned, they don’t believe it is one of the Nazgûl, since they are all imprisoned. And most tellingly, they have not yet acted against it. We can figure out quite a bit from these facts. First, they must have investigated Dol Guldur as soon as they became aware of the evil there, and identified its master to their satisfaction. And they must have concluded that he was someone ultimately non-threatening to Middle-earth at large — not a Dark Power, but a mere orc chieftain or descendent of Black Númenoreans. This in turn gives us a time frame for his first appearance in this version of the history — within an orc or human lifetime of the present, whereas in the book he’s been doing his thing in Mirkwood for over 1800 years and is responsible for the forest (formerly called Greenwood the Great) becoming evil.
And now we know enough to answer one of our major questions. Just as in the book, it must have been Gandalf who first investigated Dol Guldur to try to identify its master, and that’s what he was doing there 91 years previously when he encountered Thráin. This version of the history thus combines Gandalf’s two visits to Dol Guldur — his initial unsuccessful investigation of 2063, and his successful one of 2850 — into one. In this revision, he succeeded in identifying the nature of the evil in Dol Guldur on his first try, and reported his finding back to the Council… but he got it wrong. All we have to do is figure out whom he believed was in charge there.
Hmm… is there anything else we know, something I may have left out of the above recap for phony dramatic effect? Yes, we know (from the figurine character descriptions) that Bolg is the overseer of the dungeons of Dol Guldur. How old is Bolg? He’s the son of Azog, who in the book is slain at the Battle of Azanulbizar in 2799. Unless the orcs have sperm bank technology (credible only in a Rankin-Bass adaptation), Bolg was alive when his father was killed (even if only in utero). So when Gandalf investigated the first reports of an evil presence in the ruin in Mirkwood, Bolg was at least 50, plenty old enough to have been enlisted by Sauron as a lieutenant. (It’s also worth noting that Bolg is at least 141 when he is killed in The Hobbit in 2941; I believe this is the only orc lifetime established by Tolkien.)
So when Gandalf found Thráin in the dungeons of Dol Guldur, Bolg was not only there, he was the character Gandalf was likeliest to encounter. It’s perfectly reasonable that Gandalf could think he was in charge of the place. And that’s why Bolg has been made Sauron’s lieutenant (by both Sauron and the screenwriters): so that Gandalf and hence the White Council could think he was the master of Dol Guldur. And to return to an earlier point now that we’ve solved this riddle, it’s entirely credible that the Wise would not summon an army to drive Bolg from Mirkwood. He represents no long-term threat, Mirkwood is already a place that prudent people avoid, and there are plenty of other evil things in the world. From their point of view, he’s like Saddam before he acquired imaginary weapons of mass destruction; just one bad guy of many, and you can’t take them all on.
