The long middle

The two centuries after the Escape were anything but quiet: riots, reforms, disasters, booms, a secession and, from about 2380, the Mirror Race, alongside the new destinations. The blocs' frontiers barely moved; almost everything else did.

The Renewal Century (2300–2400)

• The Renewal Riots (2300s–2330s). Early brain renewal is scarce and expensive; riots break out in cities where the rich stop ageing and the poor do not. The Renewal Compact of 2338 gives Settlement citizens and residents alike an equal ration of brain renewal, paid for in licensed compute. The Mandate's officials, watching, guarantee their own equal ration within the decade.
• The Vesper Runaway (2311). A renewal magnate's private system, built close to Vault level without Vault engineers, seizes compute, money and factories across the outer Belt for eleven weeks before a joint fleet cuts its habitat's power (see Why it mostly works, in Recursive self-improvement).
• The birth cap (2340s). Population rebounds as lives lengthen. Earth caps itself near eight billion, by treaty between the blocs, and most Settlement polities introduce licensed parenthood; the first Line founders refuse and begin moving off-world.
• The Parasol Drawdown (2330–2401). With carbon drawdown working, stratospheric aerosol injection is stepped down over seventy years to avoid termination shock. The blocs quarrel bitterly over the pace; the last aerosol flight lands in 2401.
• The Grey Year (2371). A VEI-7 eruption in 2371 cools the planet for two years and causes the worst harvests since the Long Heat. Parasol critics call it nature's own aerosol; everyone else calls it a warning.
• The trigger (c. 2380). The Vaults show that an array of sunlight-collecting mirrors can be built near Mercury, and forecast that no rival will hold back, so every bloc races. The first self-replicating seeds run near Mercury from about 2390, two or three per bloc, and rivals follow one to fifteen years behind (see The Mirror Race).
• The Tolstoj Burn (c. 2387). The Open Cities move first. Their untested seed turns its mirrors on its own station in Mercury's Tolstoj Basin, and hundreds of crew die, most of them Raised minds working under Open City contracts (see Who moved first, in The Mirror Race).
• The Rotation Laws (2380s). By now the first renewed have held office for decades, and inheritance has stalled because nobody dies. Threshold polities cap tenure in office at fifty years and time-limit inherited property — a jubilee for an age of long lives. The Mandate's 25-year Council terms came first; the Settlement borrowed the idea.
• Freehold becomes a bloc (c. 2390). Raised enclaves have spread across the solar system since Freehold was founded in the 2250s, because a Raised mind needs no air, food or gravity. The Mirror Race makes their crews indispensable on Mercury, and the Tolstoj Burn shows what it costs them to work on others' terms. Three years later the enclaves federate under Freehold's name, buy their independence from the Open Cities and sign the Sealing Treaty, the first signatory without a Vault, and their crews work the blocs' factories for a share of each array's power (see Freehold and the Raised cities, in Kinds of mind).

The Belt Ascendancy (2400–2497)

• Tube physics and the Halcyon Breach (2410, 2418). The first test tube opens, a Mirror Race prestige project. No mirror array of 2410 collects more than about 30 GW and its two anchors draw about 200 GW, so it runs for eleven days on power stored from an early array's beam over about six years (see The Mirror Race). Eight years later comes the Halcyon Breach, when a gatekeeper team smuggles replicator designs from the Mandate's Vaults to an Open City faction. The Open Cities entered the race on replicator designs of their own; they stay in it on Halcyon's (see Superintelligence in 2497, in Recursive self-improvement, and The Mirror Race).
• The Caloris Runaway (c. 2430). An Open City seed on Mercury slips supervision and builds outside its licence on smuggled licensed industrial controllers, and the race reaches its crisis (see The Mirror Race).
• The living moon (2430s–2440s). Sun-lens telescopes find oxygen air on a moon of Gliese 876 b, the Lifeboat's destination, and its spectrum shows the oxygen is biological (see Life beyond Earth).
• The Ore Secession (2441–2449). By the 2440s the Belt is divided between the blocs: Open City charter worlds, the largest share, Settlement charter cities, the Parishad's own habitats and a few Mandate mining habitats. The Open City charter worlds and the Settlement charter cities, with the Line habitats among them, break away together. The Settlement's charter cities reject its resource levies and Earth's veto over their charters. The Open City charter worlds reject councils on Earth where money wins the votes, and where the fortunes that outvote them are betting on the Open Cities' own array, which will soon undercut the Belt's fuel monopoly. No power on Earth backs them. The Open Cities and the Settlement fight to keep their worlds, mostly with autonomous drones and the sabotage of fuel shipments, while the Mandate and the Parishad keep their own habitats out of the war. Nobody can stop it: the Belt refines and ships the fuel that every inner world and most fleets burn. Earth, Mars and the Moon have water of their own, but their refineries closed generations ago, undercut by the Belt's, and the tankers and Saturn's skimmers belong to Belt firms. Every blockade starves the blockaders first, and building new refineries at home or new skimmers at Saturn would take decades. It ends with an independent Belt Republic: the first great power outside the blocs. Freehold, the Raised bloc, backs the breakaway: its Belt enclaves support the other settlements and its crews refuse to work for the blockaders, and the Republic's founding law lets Raised citizens hold signing offices in return. It also stops the Elevator for six years (see The Elevator, in Reaching outward).
• The Ceres Letter (2440s). In the Ore Secession the breakaway Belt's council publishes a single orbital trajectory: a 30,000-tonne rock that could reach Earth in nine years. It threatens nothing in words, and the rock is never moved. Nobody forgets that it could have been, and the Concord Accord's Rock Clause answers it (see The Rock Clause, in The Mirror Race).
• The Concord Accord (2452). The array treaty registers and watches the arrays, splits the keys to Vaults and emitters, and seats the Anchorage at the Landing with six members: the Settlement, the Mandate, the Parishad, the Open Cities, the newly independent Belt Republic and Freehold, the Raised bloc, which has no Vault and is inspected instead (see The Mirror Race). The Belt signed only if its secret Vault was accepted as it stood. The blocs agreed, because a Belt outside the treaty with an uninspected Vault was worse. It is the only Vault built outside the caps that the treaty recognises. The same decade the Accord declares Gliese 876 b's living moon protected.
• The Kinship Question (2450s). The Belt's independence turns an old argument into a question of citizenship: do people genetically adapted to other worlds keep full rights to migrate to Earth? Earth decides yes, grudgingly (see Designed children, in Ageing slowed, not ended).
• The Mercury Storm (c. 2457). Mercury takes the hardest blow from every solar storm aimed its way. A storm larger than the White Night kills crews on Mercury and in ships caught in transit, most of them Freehold's Raised crews, and fries the arrays' industrial controllers, the race's bottleneck, so every bloc's array loses years of growth while the inspected fabs make replacements. Freehold renegotiates its share of every array afterwards. For a few weeks the blocs share repair data; then they stop. The Accord's Storm Protocol follows in 2460 (see The Storm Protocol, in The Mirror Race).
• The Open Cities link their Vaults (2460s). After the treaty, the Open Cities link their small Vaults for the first time, with Vault engineers hired away from the Settlement and the Parishad (see The Open Cities, in Politics).
• The colony fleets (2470s). The Mandate sends three light seed ships, to Barnard's Star, Epsilon Eridani and Tau Ceti; Line money sends one to Teegarden's Star; the Belt Republic sends one to GJ 1002, beyond the reach of the Lifeboat Laws — a second scandal the Settlement can do nothing about. Array-powered lasers push all five to about 9% of light speed, and all must brake with fusion. None arrives before the 2540s (see Reaching outward).
• The Brahmaputra Crisis (2470s). In a drought year the Mandate holds back the river behind its Tibetan dams, and both blocs put their arsenals on alert before the water is released: the standoff's closest call on Earth (see The Parishad).
• Proxima's thread (2483). The thread probe launched from Earth in 2440 reaches Proxima, and the colony can talk to Earth within minutes, though Earth's replies still take more than four years (see The Corridors).
• The bloc elevators (2488, 2496). Unwilling to depend on a shared cable after the Elevator Crisis, the Mandate opens its own elevator in the Indian Ocean and the Settlement its own in the Atlantic. The Elevator's long decline begins.
• Sanctions on the Open Cities (2490s). For 150 years the Settlement and the Mandate tolerated the Open Cities' refusal to cap births, because the Open Cities hold the Elevator's platform. With the Mandate's elevator open in 2488 and the Settlement's under way, and Open City numbers estimated past their treaty share for the first time, both begin sanctioning them to make them keep their share of the birth cap (see Where the wealth is, in Economy).
• Freehold's last human signatory (2496). Freehold, the Raised bloc, sees its last human signatory retire; every signing office there is now held by a Raised citizen (see How the Raised became citizens, in Kinds of mind).

Slow changes underneath

• Language. Latin became the mutually unintelligible Romance languages in about a thousand years. After nearly two centuries apart (its ship left in the 2310s), with contact that came late and runs one way, Proxima Common is already drifting from Earth's languages; tools hold the worlds together linguistically.
• Bodies. Engineered adaptation is turning the people off Earth into populations that look, and increasingly are, biologically distinct, by world as well as by bloc.
• Climate. The parasol is history; its politics are not (see The Long Heat).
• Faith. Stewards, Remembrancers and Meridianists are joined by faiths born off Earth, several centred on the Raised.
• Technology. After the Escape, progress is mostly refinement, except where the Mirror Race forces the pace. The Vaults produce theory faster than humans can test it, so the frontier is set by experiment, not ideas.
• Power. From nations to blocs; from Earth to the worlds off it; from states to Lines; from the founders to whoever can still claim to remember them.

Who tells this history

Historians disagree about what saved humanity. The Settlement school credits the Threshold and the Slow Lane. The energy school credits cheap power. The redistribution school credits the rationing of the Contraction. The Vault school credits the machines. The Mandate's historians credit the Mandate: order, full granaries and rulers who could not afford to fail. The newest, the deterrence school, credits fear: the Shared Question kept the bombs unused, and since 2452 every habitat being within reach of someone's sun has kept the mirrors still. Wend helped write the Settlement's official history — so its account, too, favours one explanation.