World Peace Day 1999Tuesday, September 21
World Peace Day — officially The International Day of Peace — is observed annually on September 21. It is dedicated to world peace, specifically to strengthening the ideals of peace, both within and among all nations and peoples. Hopefully, it will become the occasion for a temporary ceasefire in combat zones for humanitarian aid access.
The International Day of Peace was established in 1981 by resolution 36/67PDF document of the United Nations General Assembly to coincide with its opening session, which was held annually on the third Tuesday of September. The first Peace Day was observed in September 1982.
In 2001, the General Assembly adopted resolution 55/282PDF document, which established 21 September as an annual day of non-violence and cease-fire: (...) the International Day of Peace shall be observed on 21 September each year, with this date to be brought to the attention of all people for the celebration and observance of peace.