Political map of East Asia and the Western Pacific 13 April 1941 (Franco-Thai War): Thailand saw the French capitulation to Japan (Japanese invasion of French Indochina) as weakness, seizing the opportunity to regain lost territories by invading French Indochina (Franco-Thai War). The Japanese quickly put a stop to this war, but supported Thai claims at the ensuing peace treaty. With its focus now on the south, Japan signed a neutrality pact with the Soviet Union (Soviet-Japanese Neutrality Pact).