What eastern European border was disputed between it's two nations after World War I, was re-established in 1990 as an identical version of its former self, changed only in the name of one of it's nations?
Suwałki Region: Suwałki Region (Polish: "Suwalszczyzna" , Lithuanian: "Suvalkų kraštas, Suvalkija" ) is a small region around the city of Suwałki (known in Lithuanian as "Suvalkai") in northeastern Poland near the border with Lithuania. Suwałki Region:  The territory was disputed between Poland and Lithuania after World War I.
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