(i) Poul Anderson, "The House of Sorrows"; The Shield Of Time, Part Six, "Amazement of the World."
There was an agricultural revolution but not a later scientific revolution. Therefore, there were no political, industrial, technological or cultural revolutions. Societies continued to farm and fight.
(ii) Anderson, Maurai and many others.
A nuclear war or other catastrophe destroys technological civilization but it can be rebuilt.
(iii) SM Stirling, Emberverse.
The Change ends technological civilization and it cannot be rebuilt. What happens next? I am finding out. What caused the Change? We might find out.