The Renewal Century · The Next Five Centuries

Renewal Riots, the birth cap, the Parasol Drawdown, the Grey Year, the trigger.

Read more in The long middle

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).