Two events on 23 March 1939 shattered Beck’s illusions. On that Thursday Germany signed a treaty with Slovakia, putting the armed forces of the new puppet republic under Hitler’s control; and on the same day Germany at last struck in the north, occupying Memel and a strip of land extending 150 kilometres along the right bank of the river Niemen. From the outer balcony of the city’s neo-classical theatre Hitler personally proclaimed ‘the Memel territory reunited with the German Reich’.
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For the Baltic nations ‘Memel’ was more ominous than the two better-known pre-war crises, ‘Munich’ and ‘Prague’.
—Alan Palmer, The Baltic, (New York: Overlook Press, 2006), 316-317.