Backstory
In the BattleTech universe, the first BattleMech ever developed was the Mackie MSK-6S, described as a 100 ton box with legs. It was developed in 2439 by the Terran Hegemony, first deployed in 2443, and produced throughout the rest of the Inner Sphere after its construction plans were stolen in 2455. Significant development and refinement of the technology followed through subsequent centuries. 'Mech advancement in the Inner Sphere crested during the reign of the Star League, but slowly degraded during the protracted conflicts of the Succession Wars. Much of the infrastructure and expertise necessary to produce the most advanced models was lost, with the result that, by the early 31st century, most Great Houses were fielding models that were centuries old.
Star League-era BattleMech technology was preserved during this period of decline by a military faction later known as the Clans. Absent from the Inner Sphere for centuries, they returned in 3049 fielding 'Mechs of considerable sophistication and power. The first confirmed sighting of a Clan 'Mech by an Inner Sphere observer was that of a Timber Wolf (called the Mad Cat by Inner Sphere observers) by the legendary Phelan Kell of the Kell Hounds mercenary unit.
The Clan invasion triggered a resurgence of BattleMech-related research and development, both in the Inner Sphere and among the Clans, leading to many new models being introduced during the 3050s and '60s.
After the collapse of the 2nd Star League in late 3067, most Battlemech manufactures were damaged or outright destroyed by the Word of Blake Jihad (Holy War). Smaller factories retooled and began manufacturing ancient designs dating back to the Age of War when Mackie was first introduced. The creation of hybrids from these ancient designs and new technologies again led to a slow progress in 'Mech development, despite the return to all-out war and the use of nuclear weaponry.
However, the collapse of the hyperpulse generator network in the early 32nd century disrupted 'Mech advancement.
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