"The Atomic Era (AE) is reckoned as beginning on 2 December, 1942, Christian Era (CE), with the first self-sustaining nuclear reactor, put into operation by Enrico Fermi at the University of Chicago. Unlike earlier dating-systems, it begins with a Year Zero—2 December, 1942, to 1 December, 1943, CE. With allowances for December overlaps, 1943 CE is thus equal to the Year Zero AE, and 1944 CE to 1 AE, and each century accordingly begins with the "double-zero" year, and ends with the ninety-nine year.
"Dates AE and CE are converted by adding or subtracting 1943; thus 1964 CE is 21 AE, and 1066 CE is reckoned as 877 PreAtomic (PA). Atomic Era dating did not become official until 2nd December, 2143, or 200 AE. The Gregorian calendar, with all defects, was adopted, merely setting back January 1st to December 2nd. It took about fifty years for everybody to agree to it, and some fanatical relgious sects opposed it to the end of Terran Federation history." - From "Future History No. 1."
As different sources give different years and dates, see Zarthani.net for a more detailed timeline and comments on the different dates. H. Beam Piper (HBP, Future History No. 1.) and John F. Carr (JFC, Terrohuman Future History Chronology) give different years for many events.
Link to the alternative timeline presented by John F. Carr. The timeline below is based on H. Beam Piper and taken from Zarthani.net.
Year AE, Year AD, Comment, Source
1st Century AE (1943-2042 AD)
0, 1943, First self-sustaining nuclear fission reaction at Chicago. HBP
2, 1945, World War II ends.
27, 1970 Kilroy, first unmanned rocket, launched by United States, lands on the Moon. HBP, EK
c29, c1972, Lunar base established by United States. EK
30, 1973, "The Edge of the Knife" (published May 1957). Khalid ib'n Hussein assassinated at Basra, anarchy and inter-faction struggles in Islamic Caliphate followed by Turkish intervention, EK
c 31, c1974 United Nations collapses. HBP, EK
32, 1975, World War III ("Thirty Days' War"). Terran Federation formed under United States leadership. HBP, EK, JFC.
53, 1996, "Omnilingual" (published February 1957). First human expedition to Mars, discovery of extinct Martian civilization. OL
c55-100, c1998-2043, Further exploration of Mars, Venus, Asteroid Belt, and Moons of Jupiter. HBP.
c60-105, c2003-48, First Terran Federation begins to crack under strains of colonial claims and counter-claims of member states; serious financial dislocations. HBP, JFC.
92, 2035, Contragravity is developed. JFC.
2nd Century AE (2043-2142 AD)
c105, c2048, Venus secedes from the (first) Terran Federation. SV, JFC.
106, 2049, World War IV begins ("First Interplanetary War"). HBP, WC. UU.
109, 2052, World War IV ends. HBP, EK, WC, UU.
114, 2057, After a "debacle in the United States," General Lanningham brings U.S. atom bomb data to South America. UU.
c119, c2062, South Africa, Australia, New Zealand, Brazil, and Argentina form the second Terran Federation, HBP, JFC.
c127, c2070, Reformed (second) Terran Federation establishes single world sovereignty when Britain becomes the last nation to join; colonies on Mars and Luna. HBP, EK, KP.
183, 2126, Dillingham hyperdrive developed.HBP].
192, 2135, First expedition to Alpha Centauri. HBP, JFC.
3rd Century AE (2143-2242 AD)
200, 2143, Atomic Era dating adopted. HBP.
History without any exact dates and years
- Terro-human interstellar exploration, colonization, and expansion begins. HBP, SV.
- Thor? discovered, Thorans? encountered, Thor Company chartered. WC.
- Loki? discovered, Lokians? encountered, Loki Company chartered. WC.
- Yggdrasil? discovered, Khooghra? encountered, Yggdrasil Company chartered. WC.
- "When in the Course—" (published in 1981)
- Freya? discovered, Freyans? encountered, Freya Company chartered. WC.
4th Century AE (2243-2342 AD)
c350, c2293, Marduk? settled. SV.
c380, c2323, Fenris? settled, Fenris Company chartered. FDP.
c390, c2333, Chartered Fenris Company goes bankrupt, most colonists evacuated. FDP.
5th Century AE (2343-2442 AD)
c480, c2423, Four-Day Planet (published in 1961). Anton Gerrit, leader of Loki enslavement, captured on Fenris. Kapstaad Chemical Products, Ltd., monopoly on Fenris tallow wax broken by Argentine Exotic Organics. The Port Sandor spaceport on Fenris "was built close to a hundred years ago, when the population was" over 200 000. FDP.
6th Century AE (2443-2542 AD)
c500, c2443, Federation forces intervene on Fenris with nuclear weapons. UU.
7th Century AE (2543-2642 AD)
629, 2572, Zarathustra? is discovered and settled. HBP, JFC, LF.
c650, c2593 Poictesme? is discovered by Genji Gartner and settled, GD, JFC.
654, 2597, Little Fuzzy (published in 1962, Fuzzy Sapiens (published in 1964) and Fuzzies and Other People (published in 1984). Terra-Baldur-Marduk Spacelines holds monopoly on travel to Zarathustra; Zarathustran Fuzzy? sapience recognized; Zarathustra reclassified from Class III to Class IV world; Zarathustra Company charter revoked. LF.
8th Century AE, (2643-2742 AD)
782, 2725, Foxx Travis born, aide to commander of Federation army elements on Kwannon? during the native revolt there and commander of the Third Fleet-Army Force headquartered on Poictesme during the System States War. JFC, CC, OS.
9th Century AE, (2743-2842 AD)
812, 2755, "Oomphel in the Sky" (published November 1960). Miles Gilbert and Foxx Travis thwart native revolt on Kwannon. Aditya discovered. HBP, JFC, SS.
839, 2782, Systems States Alliance secedes from Federation. HBP.
842-854, 2785-2797, System States War. HBP, JFC, CC.
851, 2794, Federation forces destroy city of Kindelburg on Asmodai?. CC.
855, 2798, Ten thousand refugees from Abigor? (named for a demon that could foretell the future and provide military advice) and the remnants of the System States Alliance navy flee the Terran Federation and settle Excalibur?, the first Sword World. HBP JFC SV.
c856, c2799, Franchard's Rise and Decline of the System States published. EK.
c871, c2814, Conn Maxwell born. CC.
894, 2837, "Graveyard of Dreams" (published February 1958). Junkyard Planet (also as the Cosmic Computer, published in 1963). Merlin, the fabled Federation battle computer, is discovered on Poictesme by Conn Maxwell. CC, JFC.
10th Century AE (2843-2942 AD)
c950, c2892, Aditya? abandoned by (or secedes from) Federation. SS.
11th Century AE (2943-3042 AD)
c1000, c2943, Interstellar Wars begin, a series of revolts and wars that lead to the collapse of the Terran Federation, begin. HBP, JFC, SV.
12th Century AE (3043-3142 AD)
c1100, c3043, Terran Federation completely vanished. Assuming the "dissolution of the First Galactic Empire, in the Tenth Century of the Interstellar Era" mentioned in "Edge of the Knife" actually refers to the collapse of the Terran Federation it would be some date between approximately 1092 AE (3035 AD) and 1191 AE (3134 AD). HBP, EK.
13th Century AE (3143-3242 AD)
c1200 c3143, Interstellar Wars come to an end. JFC, SV.
14th Century AE (3243-3342 AD)
1359, 3302, First Sword World ship returns from voyage to Old Federation; Aditya occupied by Morglay. SV, JFC, HBP.
15th Century AE (3343-3442 AD)
c1450, c3393, First Sword-World ships enter Old Federation space-volume. HBP.
16th Century AE (3443-3542 AD)
17th Century AE (3543-3642 AD)
c1615, c3558, Skathi? in the Old Federation is deserted by Space Vikings. SV, JFC.
18th Century AE (3643-3742 AD)
c1716, c3659, Space Viking (published in 1962-63). Lucas Trask leaves Gram for Tanith? in the Old Federation. SV.
c1723, c3666, Battle of Adhumla? between Trask's nascent League and Dunnan's Space Vikings. SV.
c1725, c3668, With support from Haulteclere? and Space Viking fleet from Xochitl?, exiled Duke Omfray of Glaspyth attempts to overthrow King Angus of Gram. Battle of Marduk between alliance of Trask's nascent League and loyalist Mardukan forces and Dunnan's Space Vikings and Makann's Mardukan usurpers. SV.
c1730, c3673, King Lucas of Tanith and Prince Simon of Marduk establish League of Civilized Worlds. HBP, SV.
19th Century AE (3743-3842 AD)
c1880, c3823, House of Bentrick on Marduk dissolves League of Civilized Worlds and proclaims (first) Galactic Empire. HBP, SS, JFC.
20th Century AE (3843-3942 AD)
1900, 3843, Imperial Era (IE) dating system begins. 20th Century AE corresponds to 1st Century IE. HBP.
21st Century AE (3943-4042 AD)
c2035, c3978, Sword Worlds added to the Galactic Empire. HBP, JFC.
22nd Century AE (4043-4142 AD)
c2150, c4093, "A Slave is a Slave" (published April 1962). Aditya conquered by the Galactic Empire. SS.
23rd Century AE (4143-4242 AD)
c2295, c4238, Rodrik VI completes consolidation of (first) Galactic Empire. HBP, JFC.
24th Century AE (4243-4342 AD)
25th Century AE (4343-4442 AD)
26th Century AE (4443-4542 AD)
27th Century AE (4543-4642 AD)
28th Century AE (4643-4742 AD)
29th Century AE (4743-4842 AD)
c2850?, c4793?, The "dissolution of the First Galactic Empire, in the Tenth Century of the Interstellar Era". EK.
30th Century AE (4843-4942 AD)
31st Century AE (4943-5042 AD)
c3050, c4993, "Ministry of Disturbance" (published December 1958). Emperor Paul XXII and Prince Yorn Travann "undertake to arouse the Empire to new efforts". JFC.
301st Century AE (31,943-32,042 AD)
c30050 c31993, "The Keeper" (published July 1957). Scholar/explorers at the height of the Fifth Galactic Empire discover that a glacial Terra was the birthplace of humanity.
EK: "The Edge of the Knife," H. Beam Piper
OL: "Omnilingual," H. Beam Piper
WC: "When in the Course&mdash,"H. Beam Piper
FDP: Four-Day Planet, H. Beam Piper
UU: Uller Uprising, H. Beam Piper
NS: "Naudsonce," H. Beam Piper
LF: Little Fuzzy, H. Beam Piper
FS: Fuzzy Sapiens, H. Beam Piper
FOP: Fuzzies and Other People, H. Beam Piper
OS: "Oomphel in the Sky," H. Beam Piper
GD: "Graveyard of Dreams," H. Beam Piper
CC: The Cosmic Computer (aka Junkyard Planet), H. Beam Piper
SV: Space Viking, H. Beam Piper
SS: "A Slave is a Slave," H. Beam Piper
MD: "Ministry of Disturbance," H. Beam Piper
KP: "The Keeper," H. Beam Piper