I was wondering whether Ukraine had distinct borders before 1918 and if it did not, how did the borders during the USSR period were determined
I was wondering whether Ukraine had distinct borders before 1918.
It did not. It was a part of Russian Empire. Word "Ukraine" itself wasn't in much use until late 1917. Geographic area was usually called Little Russia = Малороссия.
Ukraine of current borders was split among several governorships - Kharkov, Kiev, Chernigov, Kherson etc. Part of Western Ukraine was included into Polish governorships. And yet another part - in Austria-Hungary (Galicia).
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