In 1932, a civilian takeover of the city of Leticia soon became an undeclared war between Peru and Colombia as the Peruvian Army moved to oppose a Colombian re-occupation.

[5] After months of diplomatic negotiations, the governments accepted mediation by the League of Nations, and their representatives presented their cases before the council.

A provisional peace agreement, signed by both parties in May 1933, provided for the League to assume control of the disputed territory while bilateral negotiations proceeded.

[8] Peru, as a founding member of the UN, has had a high level of participation in peacekeeping missions, collaborating with troops commonly known as the "Blue Helmets".

In 1988, during the management of the Peruvian Javier Pérez de Cuéllar as Secretary General of the UN, the United Nations peacekeepers received the Nobel Peace Prize.