Short answers, pulled from the story.
Aragorn is a fictional character and one of the protagonists in J. R. R. Tolkien's The Lord of the Rings. He is a Ranger of the North, first introduced under the name Strider, and later revealed to be the heir of Isildur, an ancient King of Arnor and Gondor. He ultimately becomes King Elessar, the first High King of the Reunited Kingdom of Gondor and Arnor.
Andúril was forged by elven-smiths at Rivendell from the shards of Narsil, the sword of Elendil that had been broken when Elendil was killed fighting Sauron. The reforged blade was set with seven stars for Elendil, a crescent moon for Isildur, and runes along the metal. Aragorn named it Andúril, meaning "Flame of the West".
Elrond concealed Aragorn's lineage from childhood to protect him, renaming him Estel ("hope" in Sindarin) to hide him from Sauron. Aragorn's father and grandfather had both been killed, and Elrond feared the same fate for a known heir of Isildur. Aragorn maintained aliases throughout his years of service in the armies of Rohan and Gondor, where he was known as Thorongil.
Aragorn was played by the Danish-American actor Viggo Mortensen in Peter Jackson's Lord of the Rings film trilogy. Mortensen's portrayal ranked at number 15 in Empire magazine's 2015 survey of greatest film characters. Earlier, John Hurt voiced the character in Ralph Bakshi's 1978 animated film, and Theodore Bikel played him in the 1980 Rankin/Bass television production.
Scholars have proposed several historical parallels. Archaeologist Max Adams argues Tolkien drew on the Northumbrian prince Oswald, who was exiled and later retook his kingdom by defeating Cadwallon of Gwynedd. Medievalists Alban Gautier, Christopher Snyder, and Thijs Porck each suggest Alfred the Great of Wessex as a further parallel, noting his time hiding in the wilds after being attacked at Chippenham and his subsequent victory at the Battle of Edington.
Aragorn ruled the Kingdoms of Gondor and Arnor until year 120 of the Fourth Age, a reign of 122 years. He died at the age of 210 and was succeeded on the throne by his son Eldarion. His wife Arwen died shortly afterwards in Lothlorien.