Upper Saxony
It was particularly to distinguish the lands from 'Lower Saxony', a concept which arose later in popular usage (though never enforced) as a term for the original Saxon lands in north and west Germany (where Low German dialects had spread), in what is now the state of Lower Saxony, as well as the adjacent Westphalian region, Holstein and the western part of today's Saxony-Anhalt north of the Harz range (Eastphalia).
Saxony
As World War II drew to its end, U.S. troops under General George Patton occupied the western part of Saxony in April 1945, while Soviet troops occupied the eastern part. That summer, the entire state was handed over to Soviet forces as agreed in the London Protocol of September 1944. Britain, the US, and the USSR then negotiated Germany's future at the Potsdam Conference. Under the Potsdam Agreement, all German territory East of the Oder-Neisse line was annexed by Poland and the Soviet Union, and, unlike in the aftermath of World War I, the annexing powers were allowed to expel the inhabitants. During the following three years, Poland and Czechoslovakia forcibly expelled German-speaking people from their territories, and some of these expellees came to Saxony. Only a small area of Saxony lying east of the Neisse River and centred around the town of Reichenau (now called Bogatynia), was annexed by Poland. The Soviet Military Administration in Germany (SVAG) merged that very small part of the Prussian province of Lower Silesia that remained in Germany with Saxony.