The Aaland Islands were the first dispute dealt with by the League of Nations after it formed in 1920. The Islands had been given to Finland, when it gained independence from Russia in 1917, however the population was 95% Swedish.
Aaland Islanders themselves, campaigned for a union with Sweden, and in May 1920, a law was passed by Finland, granting them considerable autonomy (right to rule/govern themselves - independence) but the campaign continued.
The L of N proposed the Aaland Islands would continue to belong to Finland, but it would guarantee:
Swedish language and customs would be kept.
Appointment of Islanders governor had to be agreed by islanders.
Aaland islands would be demilitarised under the League's supervision.