Micronesia, in the western Pacific, consists of some 600 islands grouped into four states: Kosrae, Pohnpei, Chuuk (Truk) and Yap.
Occupying a very small total land mass, it is scattered over an ocean expanse five times the size of France.
Though formally independent, in 1986 Micronesia signed a "Compact of Free Association" with the US. Under this, Washington took on responsibility for defence and gained the right to set up military bases and deny other nations access to Micronesia.
In return, Micronesia received financial assistance averaging $100m per year, and the right of Micronesians to live and work in the US.
A renegotiated 20-year compact, worth $3.5 billion to Micronesia and the Marshall Islands, was signed by US President George W Bush in 2003.
Micronesia's biggest challenge is to find a way of lessening its dependence on foreign aid, with tourism seen as one possibility.
President: Peter Christian
Peter Christian - previously a senator from the island of Pohnpei - was elected as Micronesia's eighth president in May 2015.
Mr Christian has said his priority is to boost the economy by focusing on the main industry - fisheries - with tourism as an additional source of income.
He has also vowed to preserve the unity of Micronesia against an emerging secessionist movement in Chuuk, the largest and most populous island.
The president is elected every four years by Congress.
The federal government publishes a fortnightly information bulletin and each of the constituent state governments produces its own newsletter.
Some key dates in Micronesia's history:
1500 - Spanish explorers sight islands of Micronesia.
Mid-19th century - Missionary activities and coconut trade begin.
1880s - Spain fails to extend its control over the Caroline Islands, i.e. Micronesia plus Palau.
1898 - Caroline Islands come under German colonial control.
1914 - Japan occupies Micronesia.
1939-45 - Micronesia becomes major battleground during Second World War.
1947 - Micronesia comes under US administration, in the form of the Trust Territory of the Pacific Islands, which was under United Nations authority.
1970s - Northern Marianas, Marshall Islands and Palau respectively demand separate status from the islands of Kosrae, Pohnpei, Chuuk and Yap.
1979 - Kosrae, Pohnpei, Chuuk and Yap ratify constitution setting up the Federated States of Micronesia.
1986 - Micronesia signs a "Compact of Free Association" with the US, under which Washington provides substantial economic assistance in return for taking charge of Micronesia's defence affairs, including the right to establish military bases.
2003 - Renegotiated 20-year compact with US is signed.