Gandalf in Moria

[Alcuin]

In “Journey in the Dark�, Gandalf says, “Yet it will not be the first time that I have been to Moria. I sought there long for Thráin son of Thrór after he was lost.� But since Gandalf has been in Middle-earth for about 2000 years, isn’t it likely that he also entered Moria in the days of its inhabitation by Durin’s Folk, before Durin’s Bane awoke? Are we to assume that Mithrandir never visited Moria in the roughly 900 years between his arrival in Lindon and the fall of Náin I?

In the Peter Jackson movies, Saruman wants Gandalf to enter Moria, hurling snow at the Company of the Ring in the Redhorn Pass. But in the book, Gandalf agrees with Boromir that the mountain storm was caused by Sauron.

“I wonder if this is a contrivance of the Enemy,� said Boromir. “They say in my land that he can govern the storms in the Mountains of Shadow that stand upon the borders of Mordor. He has strange powers and many allies.�

“His arm has grown long indeed,� said Gimli, “if he can draw snow down from the North to trouble us here three hundred leagues away.�

“His arm has grown long,� said Gandalf.

Saruman would have good reason to prevent the Nine Walkers from crossing the mountains: their path from the pass led straight to Lórien, while keeping them to the west of the mountains meant they had to pass Isengard. But Sauron? Why would he choose to prevent them passing over, except to keep them from Lórien? Saruman was already revealed as treacherous: he had been waylaying Sauron’s agents in Eriador, and the Nazgûl had uncovered his espionage ring in the Shire. Sauron probably knew enough of Saruman’s mind to understand that if Saruman obtained the Ring, he wasn’t giving it back. What could be Sauron’s purpose to prevent the passage of the mountains, except to keep them from uniting forces with his enemy, Galadriel?

Sauron knew about the Balrog. The orcs in Moria were from Dol Guldur: the Tale of Years for Third Age 2480 says, “(circa) Orcs begin to make secret strongholds in the Misty Mountains so as to bar all the passes into Eriador. Sauron begins to people Moria with his creatures.� He must have discovered from his orcs what was lurking there, even if they did not recognize it for what it was. We have no evidence from Tolkien that the Balrog recognized any claims of overlordship by Sauron. It almost certainly knew nothing of the Ring, and likely knew nothing of the Dwarf Ring, either (it killed two of that ring’s bearers); had it discovered either Gandalf’s ring or particularly Frodo’s Ring, that could have posed a considerable risk to Sauron: the Balrog wasn’t likely to return a purloined Ring of Power, either.

We know from Reader's Companion that Tolkien’s notes indicate that Saruman posted orcs led by Uglúk on the east side of the Misty Mountains to watch for and waylay the Company of the Ring if they emerged. Did Saruman also know about the Balrog?

Finally in this (rambling) vein, what do you suppose Sauron thought once he learned the Company had entered Lórien and that Gandalf had fallen? That someone else had taken possession of the Ring – the Heir of Isildur, of whom Sauron would later learn when Aragorn looked into the palantÃ*r at Aglarond? Would Sauron blame the fall of Angrenost on Aragorn and the Ring – and the fall of Gandalf and the Balrog in Moria on Aragorn, too?