what did it do in memel?
The League Council appointed a Commission of Inquiry which  chose to cede Memel to Lithuania and give the area autonomous rights
League of Nations
 By 1923, the fate of the area had still not been decided, prompting Lithuanian forces to invade in January 1923 and seize the port. After the Allies failed to reach an agreement with Lithuania, they referred the matter to the League of Nations. In December 1923, the League Council appointed a Commission of Inquiry. The commission chose to cede Memel to Lithuania and give the area autonomous rights. 
what is league of nations? It was the first worldwide intergovernmental organisation whose principal mission was to maintain world peace. when was it formed? 10 January 1920 how many countries does it comprise? Weimar Republic, Germany, France, Egypt etc describe its symbol? two five-pointed stars within a blue pentagon. what powers does it have? preventing wars through collective security and disarmament and settling international disputes through negotiation and arbitration who is the head of the league? The Assembly, the Council, and the Permanent Secretariat. how does one become a member of it? UNANSWERABLE what is saar? It was a province formed from parts of Prussia and the Rhenish Palatinate and placed under League control by the Treaty of Versailles. what does collective security mean? A security arrangement, political, regional, or global, in which each state in the system accepts that the security of one is the concern of all, and therefore commits to a collective response to threats to, and breaches to peace. what were the weaknesses of the league? The onset of the Second World War demonstrated that the League had failed in its primary purpose, the prevention of another world war. does the league still exist? No, it dissolved itself on  31 July 1947. where was its headquarter? UNANSWERABLE
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League of Nations [SEP] Memel
The commission chose to cede Memel to Lithuania and give the area autonomous rights. The Klaipėda Convention was approved by the League Council on 14 March 1924, and then by the Allied powers and Lithuania. In 1939 Germany retook the region following the rise of the Nazis and an ultimatum to Lithuania, demanding the return of the region under threat of war. The League of Nations failed to prevent the secession of the Memel region to Germany.