BattleTech eras

Catalyst Game Labs, the current owners of BattleTech, have divided history into eras and sub-eras. The products they release are grouped in this manner.^[1]

Era	Sub Era	Years	Description
Pre-Star League	Pre-Spaceflight	Before 1950	Earliest era referenced, when humanity only resides on its planet of origin, Terra.
Pre-Star League	Early Spaceflight	1950 – 2005	Early solar system restricted spaceflight.
Star League^[2]	Age of War	2005 – 2570^[2]	The time of humanity’s first migrations off Terra, the political upheavals and the founding of the first interstellar states. In this sub-era within the consistent warfare of those other states expanding forming the Inner Sphere houses, the Terran Hegemony would form as a dominant state fielding the first BattleMech.
Star League^[2]	Star League	2571 – 2780^[2]	The time of the formation of the First Star League and it reaching the height of its power. Advancements in science and technology allow for humanity to experience 200 years of peace and prosperity across all settled worlds. However as the Periphery nations revolt the realm is torn apart and destroyed in a thirteen-year war with a coup
Succession Wars ^[3]	Early Succession Wars	2781 – 2900^[3]	The timeframe of the First and Second Succession Wars, when the Successor States of the Great Houses vied for supremacy after the collapse of the Star League. Planets and populations are decimated and most advances of the Star League are completely lost. This is due to the use of weapons of mass destruction by all factions involved. The first war ends only to have the second begin a few years later.
	Late Succession Wars – LosTech	2901 – 3019^[3]	This is the timeframe of the almost 200 year Third Succession War as the Great Houses have descended into constant low level war with each other. With most of the advances of the Star League completely lost with the first 2 Succession Wars, combat became more and more ritualized in the fashion of medieval battles or even duels in order to prevent further technology loss. This development went hand in hand with the establishment of neo-feudal societies, also reminiscent of the middle ages.
	Late Succession Wars – Renaissance	3020 – 3049^[3]	With the discovery of the Helm Memory Core and its subsequent dissemination throughout the Inner Sphere, the gradual rediscovery of lost Star League technology allowed the Inner Sphere to have a “Renaissance” of sorts. Faction militaries could now produce and replace their crippling losses to their 'Mech and armor units. With this in mind all the Great Houses begin an upswing of production right in time for the joining of 2 Houses the Federated Suns and Lyran Commonwealth into one realm and the start of the Fourth Succession War.
Clan Invasion ^[4]		3050 – 3061^[4]	Starting early in this era an invasion force attacks the coreward region of the Inner Sphere. Calling themselves the “Clans” they are discovered to be the descendants of Kerensky’s SLDF troops that exiled themselves at the start of the Succession Wars. With the aim of conquering world after world with their superior technology and military, the Inner Sphere becomes yet more motivated to not only work together, but also recover more lost Star League technology to counter the invaders. By the end of this era, the Inner Sphere houses had re-established a technological knowledge base that approximated the technological state of the Star League era.
Civil War ^[5]		3062 – 3067^[5]	This 5 year period highlights the many conflicts that burst apart after the Clan invasion ended via the Great Refusal. The Capellan Confederation begins the Xin Sheng Campaign to reclaim the St. Ives Compact, Exploiting discontent, the Black Dragon Society manipulates the start of the First Combine-Dominion War, and Federated Commonwealth of the Lyran Commonwealth and Federated Suns falls into a painful civil war.
Jihad ^[6]		3068 – 3080 ^[6]	The time period known as the Jihad refers to a major interstellar war that involved all major factions, mainly consisting of the faction called the Word of Blake attacking capitals and other, important industrial worlds to hamper their enemies' capacity to wage war. They created a "white-out" of the HPG grid that forced regional leaders to take a more active role, then manipulated those leaders to create chaos and warfare that distracted their enemies from the Word's activities. Using "hidden" armies they hit former Chaos March worlds in the vicinity of Terra, which led to the formation of the new state, the Word of Blake Protectorate. The Jihad was not only of the Word of Blake assaulting foreign powers, but also civil conflicts that erupted between states due to the chaos and the actions of the factions.
Dark Age ^[7]	Republic	3081 – 3130 ^[7]	With the Word Of Blake's defeat at the start of this era using coalition forces made possible through unifying efforts of Devlin Stone and David Lear to crush them. The formation of the Republic of the Sphere out of the ashes of the Word of Blake Protectorate created a new buffer state between the various Inner Sphere powers. Additionally the Republic set in motion a plan with the other major factions to decommission BattleMechs and other tools of warfare, downsizing armies and removing any such material from the hands of private individuals.
Dark Age ^[7]	Dark Age	3131 - 3152 ^[7]	The time since the collapse of the HPG network caused political chaos in The Republic of the Sphere that led to the militarization of Industrial Mechs and other civilian equipment. Then the steady advancement of the Great Houses and Clans themselves began to take back worlds they ceded to the Republic, as the fragmented and stumbling Republic made an easy target. Finally ending with the ilClan Trial being fought on Terra, days after the broadcasted disbanding of the Republic.
ilClan^[8]	ilClan	3152 – ???? ^[8]	The once-invulnerable Republic of the Sphere lies in ruins, torn apart by the Great Houses and the Clans. As Fortress Republic collapses, the Clans race toward Terra to create a supreme authority which will rule the Inner Sphere by any means necessary.