Summary
The Treaty of Mars is the early-31st-millennium compact between the Emperor of Mankind and the Mechanicum of Mars. Its terms made the Mechanicum a constituent estate of the nascent Imperium while preserving the autonomy of the forges, the Cult’s internal governance, and the priesthood’s exclusive authority over its own doctrine.
Key terms (paraphrased)
- The Mechanicum recognises the Emperor as the Omnissiah’s manifestation in mortal flesh, doctrinally accommodating the cult of the Emperor without forsaking the Omnissiah.
- The Mechanicum retains internal authority: forge worlds rule themselves, the Fabricator-General sits among the High Lords but is not subordinate to them in matters Mechanicus.
- The forge worlds supply the Imperium’s war material; the Imperium does not requisition forge production beyond agreed tithes.
- The Cult retains exclusive custody of its archeotech reserves.
Significance
The Treaty is the only Imperial founding document that survived the Heresy substantially intact. The Mechanicum’s loyalist remnant carried its terms forward; the schism with the Dark Mechanicum at the close of the Heresy redefined who was bound but did not annul the compact itself.
The doctrinal trick the Treaty performs is the manifestation clause: the Emperor is the Omnissiah for purposes of inter-estate relations, and the Omnissiah remains a separate object of Mechanicus worship. Most Magi consider this a precise theological statement; some consider it a careful evasion. Both readings are tolerated.