Sméagol-Gollum and the legacy of Pity.

It was some years ago that I first noted differences in the use of the names Sméagol and Gollum. Gandalf only calls him Sméagol when he is trying to persuade Frodo that he is pitiable. Frodo addresses him as Sméagol, but refers to him as Gollum. The Tale of Years in Appendix B, moreover, cleverly signals the changes in him by referring to him differently at different times. He is Sméagol until he murders Déagol for the Ring; then Sméagol-Gollum until he loses the Ring to Bilbo; and always Gollum thereafter.

2463: About this time Déagol the Stoor finds the One Ring, and is murdered by Sméagol.

2470. About this time Sméagol-Gollum hides in the Misty Mountains.

2941: Bilbo meets Sméagol-Gollum and finds the Ring. 

2944: Gollum leaves the Mountains and begins his search for the 'thief' of the Ring

2951: Gollum turns towards Mordor. 

2980: About this time Gollum reaches the confines of Mordor and becomes acquainted with Shelob. 

3001. Bilbo's farewell feast. Gandalf suspects his ring to be the One Ring. The guard on the Shire is doubled. Gandalf seeks for news of Gollum and calls on the help of Aragorn.

3009: Gandalf and Aragorn renew their hunt for Gollum at intervals during the next eight years, searching in the vales of Anduin, Mirkwood, and Rhovanion to the confines of Mordor. At some time during these years Gollum himself ventured into Mordor, and was captured by Sauron. 

3017: Gollum is released from Mordor. He is taken by Aragorn in the Dead Marshes, and brought to Thranduil in Mirkwood. 

About 20 June 3018: Gollum escapes [captivity in Thranduil's realm]

August 3018: All trace of Gollum is lost. It is thought that at about this time, being hunted both by the Elves and Sauron's servants, he took refuge in Moria; but when he had at last discovered the way to the West-gate he could not get out

13 January 3019: Gollum begins to trail the Ring-bearer.

16 February 3019: Gollum in hiding on the west bank observes the departure.

29 February 3019: Frodo descends from the Emyn Muil and meets Gollum.

11 March 3019: Gollum visits Shelob, but seeing Frodo asleep nearly repents.

12 March 3019: Gollum leads Frodo into Shelob's lair.

25 March 3019: Gollum seizes the Ring and falls in the Cracks of Doom. 

Note that from the first his identity as a Hobbit, and in particular a Stoor, like Déagol, is suggested. Note also the reference to his near repentance. Details like these disclose the hand of an author who, so far from merely portraying him as a villain, recognized his humanity, his kinship as a Hobbit, and agreed with Gandalf that Gollum's was a sad story. As the use of the different terms indicates, this author gave some thought to the journey from Hobbit to monster; and sees  the moment of final transition from Sméagol-Gollum to Gollum in his loss of the Ring to Bilbo. Even if the Prologue (14) did not inform us that the appendices were added in Westmarch in the Shire, it would be easy to guess that the author was a Hobbit with some personal connection to the story, likely a Fairbairn and a descendant of Master Samwise, who awoke at the crucial moment on the Stairs of Cirith Ungol and 'blighted' (as Tolkien himself said) Gollum's last chance for repentance. Even in that instant Sam knew he had been wrong to be as harsh as he was to Gollum. 

What the presence of these various descriptions of Gollum in Appendix B tells us is quite moving. It tells us that the pity which Frodo and even Sam came to feel for Gollum was handed down as an enduring legacy to Sam's descendants, and that among them it continued to be thought meaningful. It speaks to the forgiveness Frodo told Sam they should show Gollum since the quest could not have been achieved without him. Even if Gollum remained the villain of the story, some would remember that the sad story of Sméagol lurked behind that of Gollum.