My first followed a schism
My second preceded a war
Of a decade and a score
My third was ready for bed
Possibly done by the Reds
It is "A Throwaway Riddle" because
It's all about people being thrown out of windows. Fortunately for me, when I was defenestrated at college (earning a lifelong interest in such things), it was from a bar on the ground floor.
The First ...
... Defenestration of Prague involved the killing of seven members of the city council by a crowd of Czech Hussites on 30 July 1419 - "a schism of proto-Protestantism"
The Second ...
... Defenestration of Prague precipitated the Thirty Years' War - "a war of a decade and a score"
The Third ...
... defenestration of Prague has been used to describe the death of Jan Masaryk, who was found below the bathroom window ("ready for bed") of the building of the Czechoslovak Ministry of Foreign Affairs on 10 March 1948. It was widely believed he was murdered, either by the nascent Communist government, or by the Soviet secret services - "Possibly done by the Reds".