I developed the timeline below as an aid to game masters who might want to run a role-playing game campaign in the Middle-earth of the Peter Jackson movies. I worked out a timeline that takes into account the changes that Jackson has introduced. Most of Jackson’s alterations take place in the Third Age of Middle-earth. The main exception to that is how he ends the Last Alliance of Elves and Men that brings the Second Age to an end. Jackson sets the overthrow of Sauron immediately after the Battle of Dagorlad in S.A. 3434, eliminating the siege of seven years that would have brought about the end of the Second Age seven years later (in 3441).
A TIMELINE FOR THE THIRD AGE OF MIDDLE-EARTH BASED ON THE PETER JACKSON FILMS
Early in the Second Age, the Men known as the Edain reach the island of Númenor. Soon after, many Dwarves leaving their old cities in Ered Luin go to Moria and swell its numbers. Sauron, alarmed as the Númenóreans grow in power, constructs his stronghold of Barad-dûr in Mordor. He offers friendship to the Elves of Eregion and with their aid forges sixteen Rings of Power. The Elven-smith Celebrimbor crafts the Three Rings in secret and they remain untainted by the Dark Lord. When Sauron completes the Master Ring in Barad-dûr, Celebrimbor perceives his intent and the Three are hidden from him. Eregion is destroyed in the War of the Elves and Sauron; Elrond with the remaining Noldor of Eregion founds the refuge of Imladris. In time Tar-Minastir of Númenor sends a great navy to Lindon; Sauron is defeated and driven out of Eriador, bringing peace to the Westlands for many years.
After a century, Númenor begins to establish dominions in Middle-earth as Sauron extends his own power eastwards. This is also when he begins to distribute the Great Rings: seven to the Lords of the Seven Houses of the Dwarves; and nine to kings and heroes of Men--three of those to Lords of Númenor. In SA 2251 the Ringwraiths first appear. About this time Black Númenóreans build a fortress in the south of the Greenwood upon the hill of Amon Lanc, later renamed Dol Guldur (the Hill of Sorcery).
Over the next two thousand years the Númenóreans suffer through periods of rebellion and division until Ar-Pharazôn the Golden seizes the throne. Ar-Pharazôn sails to Umbar with a great navy to contend with Sauron for mastery of Middle-earth. Sauron, seeing the size of the Númenórean force, humbles himself and surrenders to the King. He is taken as a prisoner to Númenor where he corrupts Ar-Pharazôn and convinces him to defy the Ban of the Valar. Eru Ilúvatar brings about the Change of the World. Númenor is destroyed and Sauron is driven formless back to Middle-earth.
The surviving people of Númenor found the Realms in Exile: Gondor and Arnor; Sauron returns to Mordor where he regains his power over the next hundred years. The Dark Lord attacks Gondor, and the Last Alliance of Elves and Men is formed. In the year 3434 of the Second Age the Dark Lord Sauron is defeated when Isildur cuts the Ruling Ring from his hand and the Third Age of Middle-earth begins. The stronghold of Dol Guldur was abandoned by the Númenóreans between the time of the destruction of Númenor and the end of the Second Age only to be occupied for a time by the Greenwood Elves. Jude Fisher, in his bookThe Hobbit: The Desolation of Smaug Visual Companionwrote: “Once the Elves of the Woodland Realm frequented this region, but growing tensions with the Elves of Lórien in the west persuaded them to abandon the fortress and it had long fallen into disuse.”
The Third Age
0002 - Isildur is slain by Orcs in the Gladden Fields. The One Ring is lost.
0087 - Legolas, son of Thranduil, is born.
0109 - Elrond weds Celebrían, daughter of Celeborn.
0130 - Birth of Elladan and Elrohir, sons of Elrond.
0241 - Birth of Arwen Undómiel.
1000 - About this time, the Istari arrive in Middle-earth. Lord Círdan gives the Ring of Fire to Mithrandir (Gandalf the Grey).
1050 - Gondor is at the height of its power. The Periannaith are first mentioned in records with the coming of the Harfoots to Eriador.
1150 - The Fallohides enter Eriador. The Stoors come over the Redhorn Pass and move to the Angle or to Dunland. The Wizard Radagast the Brown establishes his home of Rhosgobel at the edge of the Greenwood near Dol Guldur.
1300 - The Nazgûl reappear. The chief of these comes north to Angmar. The Periannaith migrate westward; many settle at Bree.
1409 - The Witch-king of Angmar invades Arnor. King Arvaleg I slain. Fornost and Tyrn Gorthad are defended. The Tower of Amon Sûl destroyed.
1432 - King Valacar of Gondor dies and the civil war of the Kin-strife begins.
1437 - Burning of Osgiliath and loss of thepalantír.
1601 - Many Periannaith migrate from Bree and are granted land beyond Baranduin (the Brandywine River) by Argeleb II.
1630 - About this time, Stoors from Dunland enter the Shire.
1636 - The Great Plague devastates Gondor. The plague spreads north and west, and many parts of Eriador become desolate. The Periannaith survive but suffer great losses.
1974 - End of the North Kingdom. The Witch-king overruns Arthedain and takes Fornost.
1975 - Arvedui drowned in the Bay of Forochel. The Witch-king is nearly defeated at the Battle of Fornost until the rest of the Nine come to his defense. The Kingdom of Angmar is pushed back, but persists for another five centuries. At some time between 1975 and 2300 Angmar makes war upon the Woodland Realm and the Elf-queen is killed in Gundabad.
1976 - Aranarth takes the title of the Chief of the Dúnedain. The heirlooms of Arnor are given into the keeping of Elrond.
1979 - Bucca of the Marish becomes first Thain of the Shire.
1980 - A Balrog appears in Moria and slays Durin VI.
1981 - Náin I slain. The Dwarves flee from Moria. Many of the Silvan Elves of Lórien flee south.
1999 - Thráin I comes to Erebor and founds a dwarf-kingdom 'under the Mountain'.
2000 - The Nazgûl issue from Angmar and besiege Minas Ithil.
2002 - Fall of Minas Ithil, afterwards known as Minas Morgul. Thepalantíris captured.
2050 - Eärnur, the twenty-third king of Gondor, answers the challenge of the Witch-king and is assumed to have been killed, leaving Gondor without an heir. At some time after this, the Witch-king returns to Angmar.
2210 - Thorin I leaves Erebor and goes north to the Grey Mountains where most of the remnants of Durin's Folk are now gathering.
2340 - Around this time, the Wood-elf Tauriel is born.
2463 - The White Council is formed. The Nine are defeated by the Dúnedain (possibly with the aid of the Council) and are entombed at the High Fells in Rhudaur. 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.
2509 - Celebrían, journeying to Lórien, is waylaid in the Redhorn Pass and receives a poisoned wound.
2510 - Celebrían departs over the Sea. Eorl the Young wins the victory of the Field of Celebrant. The Rohirrim settle in Calenardhon.
2570 - About this time Dragons reappear in the far North and begin to afflict the Dwarves.
2589 - Dáin I slain by a Dragon.
2590 - Thrór returns to Erebor. Grór his brother goes to the Iron Hills.
2670 - Tobold plants 'pipe-weed' in the Southfarthing.
2763 - Balin son of Fundin is born.
2772 - Dwalin son of Fundin is born.
2774 - Óin son of Gróin is born.
2776 - Birth of Thorin II.
2781 - Frerin younger son of Thrór is born.
2783 - Glóin son of Gróin is born.
2790 - Dís daughter of Thrór is born.
2815 - About this time, Thranduil commissions the crafting of the Necklace of Lasgalen in memory of his lost queen.
2820 - The coming of Smaug to Erebor. About this time Sauron occupies Dol Guldur.
2829 - Battle of Moria. Thrór and Frerin are slain, Thráin II is captured and taken to Dol Guldur.
2832 - Thorin leads his people to the Blue Mountains. Sometime between 2840 and 2858 Dís weds.
2859 - Dís gives birth to Fíli.
2864 - Kíli is born.
2880 - Smaug is sighted outside of Erebor.
2891 - Birth of Gilraen, woman of the Dúnedain of the North.
2913 - Arathorn II, son of Arador (fourteenth Chieftain of the Dúnedain of the North), weds Gilraen. Birth of Denethor II son of Ecthelion II in Minas Tirith.
2915 - Aragorn son of Arathorn II is born on March 1.
2917 - Arathorn II slain. Gilraen takes Aragorn to Imladris to be raised as 'Estel' by Elrond.
2935 - Elrond reveals to 'Estel' his true name and ancestry. Aragorn meets Arwen and goes out into the Wild. Around this time Sauron occupies Dol Guldur and frees the Nine from their tombs in the High Fells.
2939 - Thorin meets Gandalf in Bree. About this time might be when Gandalf and Aragorn first meet and become friends.
2940 - The Quest of Erebor; the White Council drives the Necromancer out of southern Mirkwood; the Battle of Five Armies. Thorin, Fíli and Kíli are slain.
2941 - Bilbo returns to Bag End. Aragorn begins his period of great journeys and errantries.
2951 - Sauron declares himself openly in Mordor and sends three of his Nazgûl to restore Dol Guldur.
2953 - The last meeting of the White Council. Saruman takes Isengard as his own and begins fortifying it.
2959 - Denethor weds Finduilas of Dol Amroth.
2961 - Birth of Boromir son of Denethor II.
2963 - Samwise Gamgee is born. Théoden becomes King of Rohan.
2964 - Aragorn leaves the service of Ecthelion II, the Steward of Gondor. Aragorn and Arwen are reunited in Lórien.
2965 - Meriadoc Brandybuck is born.
2966 - Faramir son of Denethor is born.
2967 - Death of Ecthelion II. Denethor II becomes Steward of Gondor. Birth of Frodo Baggins.
2971 - Finduilas dies young.
2972 - Balin leaves Erebor to found a new dwarf-colony in Moria.
2973 - Peregrin Took is born.
2974 - Éomer Éomund's son is born in Rohan.
2977 - Balin is slain and the colony is destroyed.
2978 - Éowyn sister of Éomer is born.
2979 - Drogo Baggins and his wife Primula drown in a boating accident on the Brandywine, leaving their only child Frodo an orphan.
2983 - Saruman dares to use thepalantírof Orthanc and becomes ensnared by Sauron who possessed the Ithil-stone. He becomes a traitor to the Council and he becomes curious about Gandalf's interest in the Shire.
2988 - Bilbo Baggins adopts his young cousin Frodo as his heir.
2990 - Bain son of Bard becomes King of Dale.
2991 - Death of Gilraen.
3000 - Bilbo celebrates his eleventy-first birthday and secretly leaves for Rivendell.
3001 - Frodo Baggins takes the One Ring to Rivendell. The Fellowship of the Ring is formed.
Notes: I think that this should be fairly accurate for the films, although there is some guesswork involved. One has to play around with some birth years to make certain ages come out right (for example: those of Aragorn, Sam, Merry and Pippin). This does require us to disregard the birth years given for Thorin and his siblings on the tapestry that Bard locates in Dale, but I consider that to be an artifact carried over from Tolkien's genealogy for the Line of Durin.
I have adopted Tolkien’s timeline for the delving of the halls of Thranduil in the Woodland Realm, simply changing the reasons for the Wood-elves’ relocation to align with Jude Fisher’sThe Hobbit: The Desolation of Smaug Visual Companion(though even that had its origins in Tolkien’s writings).
King Eärnur of Gondor rode out in the year 2050 to meet the challenge of the Lord of the Nazgûl and was never seen again by mortal eyes. He may have been tormented and killed outright by the Witch-king. On the other hand, Eärnur might have been tortured with a Morgul-knife and transformed into a Fell Wraith enslaved to the Wraith-lord. Perhaps he was even placed in command of Minas Morgul for a time in his master's absence.
The Battle of Moria could alternately be set as late as TA 2840 by paraphrasing Gandalf's conversation with Thorin at the Unexpected Party ofThe Hobbit: "And Thrain your father [was lost] on the twenty-first of April, a hundred years ago last Thursday, and has never been seen by you since". That means that Thorin could have led his people to the Blue Mountains a bit later (probably around the year 2843) and that Dís would likely have married sometime after that (but still before the year 2859 when Tolkien reports the birth of Fíli).
Finally, it is possible that the adult Aragorn does not first encounter Gandalf until the year 2941, after Bilbo and the wizard return to the Shire. If this is the case then his period of great journeys and errantries should be adjusted to be 2942-2965, culminating with Aragorn and Arwen plighting their troth in Lóthlorien on the evening of Midsummer in the year 2965.