How successful was the League of Nations ?

After WW1 Poland and Lithuania were made. Vilna was the capital of Lithuania but most people wanted to be Polish. Poland took control with it's army and the League did nothing.

It was on the border of Poland and Germany with Germans and Poles both living there. A vote took place and Germany got 60% but the League split it into regions depending on the voters. Both accepted this but neither were happy.

Sweden and Finland claimed the land and threatened war. The League gave it to Finland but no forts could  be built on it. They were successful in resolving the conflict.

An Italian general was murdered on the Greek border and Mussolini invaded Corfu killing 15 people. The League made him withdraw his troops but gain compensation once the murderers were found. He complained and the conference of Ambassadors gave him his money.

Greek soldiers were murdered on the Bulgarian border and Greece invaded. The League orered them to remove their soldiers and pay compensation. Greece thought they were being hypocritical after how they dealt with Mussolini and Corfu

The American economy crashed and they wanted back the loans they had given other countries meaning they all faced an economic depression too. The League was powerless.