The US military government that ruled Korea south of the 38th parallel between Japan's surrender and the founding of the Republic of Korea — the southern half of the great-power division that produced the two Koreas.
Dissolved 15 August 1948 when the Republic of Korea was proclaimed under Syngman Rhee; the existing south-korea record (start 1948) succeeds it directly.
The standard scholarly account of Korea 1945-48 — the USAMGIK period is its core subject. Verified on Open Library (Cumings, 1981).