I wrote the following as my final essay for my author studies class of C.S. Lewis and J.R.R. Tolkien. I've incorporated the suggestions my professor made (mostly removing unnecessary citations) and thought I'd post it for you readers on the interweb. Let me know what you think, LotR fans!
One of the most dynamic characters the reader encounters in The Lord of the Rings is that of Aragorn, son of Arathorn. There are two senses in which this character develops throughout the series, the first being a sort of traditional character growth, most of which had already taken place well before the founding of the fellowship, and the second resembling more of an unveiling of the character to his companions, which takes place over the year or so from when he meets the hobbits to when he is crowned King of Gondor. Naturally, the two developments are related to one another, but the distinction is fairly significant, and becomes apparent if one realizes that much of Aragorn's development takes place long before he met Frodo and the Hobbits in Bree, and is recorded after the closing lines of the novel in its appendices.
Aragorn, we learn in Appendix A of The Lord of the Rings, began his life under a false name with no knowledge of his true kingly lineage. He spent his first twenty years under the name Estel, or “Hope.” Little is said of this time, except that Elrond came to love him as a son, and that the period ended when Aragorn “returned to Rivendell after great deeds in the company of the sons of Elrond; and Elrond...saw that he was fair and noble and...would yet become greater in body and in mind.” At this point, Elrond rewarded Aragorn with his true name, true heritage, and many—though not yet all—of the heirlooms of his house. Shortly thereafter, Aragorn first sees Arwen, the daughter of Elrond, and falls immediately in love with her. This is perhaps the only brash action which is attributed to Aragorn, who throughout the novel itself makes every decision cautiously and thinking heavily of the consequences. However, even if Aragorn did not think fully through the repercussions of his love, he did stick by his decision, demonstrating even from an early age a genuine sense of commitment.
There are two major spans of time between Aragorn's first loving Arwen and his appearance in The Fellowship of the Ring. The first is a space of about thirty years, after which Arwen sees Aragorn come into his own and strong (not to mention clad in Elvish clothes). Though we are not told all of Aragorn's deeds in this time, we can gather from chronologies that it was in this time that he met and befriended Gandalf, and that he served both the King of Rohan and the Steward of Gondor in disguise. We learn four attributes of Aragorn's character from these facts. First of all, he keeps high company, since he manages to befriend a member of the Maiar. Secondly, though he knows his high birth and has been given such tokens as could prove his rank, he chooses to still serve until the time is right for his ascension. Thirdly, though he serves, he offers no one his allegiance, or else he would not have served two rival, though friendly, kingdoms of men. Fourth and finally, he has learned well the value of secrecy, following Elrond's lead in hiding his heritage. Arwen, seeing these changes in him, falls in love with him and the two commit to faithfulness to one another.
After receiving Arwen's pledge of love, Aragorn again turned to traveling and adventuring. He spent the next thirty-eight years protecting the North as a Ranger, taking time for such individual tasks as hunting and jailing Gollum, before meeting with the hobbits in Bree. At some point in this period, he also met Bilbo, and began his friendship. It is likely from this friendship that Aragorn learned to appreciate hobbits. This period more or less solidifies Aragorn's kingly nature, and the majority of his development after this point is the unveiling of which I spoke earlier.
When Aragorn first meets the hobbits, he is not trusted, having all but completely hidden his goodness beneath a rough exterior. Butterbur, who has seen him many times, mistrusts him and warns the Hobbits to avoid him out of genuine concern. He appears, at first, merely a gruff man of the wilderness, skilled in fighting and perhaps in hunting, but with few other attributes certain. After Frodo is stabbed at Weathertop, however, he shows himself also to know something of healing, even if it is only enough to slow the effect of the Nazgûl's blade until they could reach Elrond in Rivendell. He continues to quest throughout the world after they reach Rivendell, and reveals his true identity to more companions as they set out to destroy the Ring. But the next significant unveiling is that he was wiser even than Gandalf in at least one sense: he knew tragedy would befall the Fellowship if they travelled through Moria, and for lack of regard for his counsel, Gandalf was lost. However, this is also what forces the next change in Aragorn—whereas before he was able to rely on his wise friend for leadership, now he was forced to take his place as a true leader. Where at first he is hesitant, pulled by alternating desires, he ultimately makes a bold decision and begins to use his inborn authority to lead.
Aragorn, in leadership, continues to reveal his name at need, in such cases as when Éomer demands the company identify themselves in Rohan. When Gandalf returns from the dead, Aragorn yields leadership back to him, not so much out of reliance, as he apparently did at first, but more out of respect. When they must part ways next, Aragorn does not bemoan their fate. Indeed, very little is said of Aragorn at all, whose dialog is sometimes recorded even without a hearer. I would therefore consider it reasonable to say that he was entirely at peace with the parting.
Once Gandalf has departed, Aragorn takes possession of the palantír and takes it from Sauron's control, showing that he, unlike Saruman, could not only withstand but overpower the will of the Dark Lord. From this point on, few of his choices are really developments or unveilings for the reader, only the natural actions of a man who knows that the times are grim and his destiny is high. Even in his decision to rally the dead army and his decision to ride, perhaps to his death, against the gates of Mordor, seem in keeping with the man we have met already. After the victory, he seeks a sign by which to claim his rightful kingship and his queen, but he himself is already ready for this, it cannot be called “change.” The only real change that remains in him is long after the events concerning the Ring are over—in his final days, Aragorn chooses to meet his end as he grows weary, not staying even for his love for Arwen. This is the final and most important change, as it allows him to return to the legacy of his forebears, not only men of Gondor, but the mighty Númenoreans as well.