International Day of UN Peacekeepers: 29 May

The International Day of UN Peacekeepers is observed across the world on May 29, with an aim to honour more than 3700 peacekeepers who have lost their lives while serving the United Nations since 1948, including 129 who died in 2017.

The theme of the International Day of UN Peacekeepers 2018 is ‘UN Peacekeepers: 70 Years of Service and Sacrifice’. The first UN peacekeeping mission was established on 29 May 1948. The day was first celebrated in 2003.
Source- The United Nations