Entire Central Europe including people known today as Germans, Poles, Czechs and other, lived in a unified Commonwealth/Confederate state of a similar structure to modern Swiss Confederation, called Leh/Reich, that was destroyed by Tatar invasion followed by the Holy Roman Empire conquest about 1000 years ago.
Germany: The biggest part of Leh/Reich was Germany: Germans have been imposed the false national identity twice, which completely wiped out their (our) true ancient history and true ethnicity. First about 1000 years ago, they have been latinised, feudalised and Christianised by the Holy Roman Empire and the Catholic Church. About 500 years ago Germany was again imposed a false national identity using the newly invented/codified Hochdeutsch language during the Reformation period by the Lutheran Evangelical Church, which standardised the new official language while at the same time wiped out the previous local languages, mostly Slavic, Dutch and other dialects.
Poland and Czechia (Moravia): – Poles and Czechs have been latinised, feudalised and Christianised like Germans, also about 1000 years ago during the Holy Roman Empire crusades and conquests, but their local dialects and languages were not wiped out because the influence of the Roman Catholic Church and the reformed Christian offshoots like Hussite, Calvinist and other movements were not as strong and as entrenched as in Germany and were not as focused on the language as Martin Luther was.
The trace of the common history of Europe lies in our genetics, which I will list in the order of the migration of the so-called “Caucasian” tribes from the East (Asia) going Westwards, beginning about 7500 years ago with the first haplogroup “I”:
I = true oldest “germanic” people (nowadays mostly Dutch-Deutsch, Danish-Datske, other Scandinnavian, and Illyrian along Danube river in Austria, Serbia and Romania)
R1b = West Slavic (Venedan, Vandal, Celts, Gaul),
R1a = East Slavic (known as: Scythian, Sarmatians, Ląchy, Laiken, Polanie)
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