Answer:
Post-classical history (also called the post-antiquity era, post-ancient era, or pre-modern era) is a periodization commonly used by the school of "world history" instead of Middle Ages (Medieval), which is roughly synonymous.[1] The period runs from about AD 500 to 1450 though there may be regional differences and debates. The era was globally characterized by the expansion of civilizations geographically and development of networks of trade between civilizations
He contributed to a writing called On the Heavens
Ans: It redrew the world map and reshaped many borders in Europe. The collapse of the Russian Empire created Poland, the Baltics, and Finland. The Austro-Hungarian Empire dissolved into Austria, Hungary, Czechoslovakia, and Yugoslavia. The German Empire became Germany, and Germany lost substantial territory outside Europe.
