The South Sudanese population is composed mostly of Nilotic peoples, and it is demographically among the youngest nations in the world, with roughly half under 18 years old. The majority of inhabitants adhere to Christianity or various Indigenous faiths. The country is a member of the United Nations, the African Union, the East African Community the Intergovernmental Authority on Development and is a party to the Geneva Conventions. As of 2019, South Sudan ranks third-lowest in the latest UN World Happiness Report, third lowest on the Global Peace Index, and has the fourth-highest score on the American Fund for Peace's Fragile States Index.