Complex sentence: Naoe Naganuma was appointed chairman of the board in December, 1945, and at that point decided to dissolve the Society, a decision that was officially approved by both the Minister of Education and Foreign Affairs.
Split into simpler sentences: Naoe Naganuma was appointed chairman of the board in December, 1945, and decided to dissolve the Society. The Society was officially approved for dissolution by both the Minister of Education and Foreign Affairs.