A republic (from Latin res publica 'public affair') is a form of government in which "supreme power is held by the people and their elected representatives". In republics, the country is considered a "public matter", not the private concern or property of the rulers. The primary positions of power within a republic are attained through democracy or a mix of democracy with oligarchy or autocracy rather than being unalterably occupied by any given family lineage or group. With modern republicanism, it has become the opposing form of government to a monarchy and therefore a modern republic has no monarch as head of state.As of 2017, 159 of the world's 206 sovereign states use the word "republic" as part of their official names. Not all of these are republics in the sense of having elected governments, nor is the word "republic" used in the names of all states with elected governments.

The word republic comes from the Latin term res publica, which literally means "public thing", "public matter", or "public affair" and was used to refer to the state as a whole. The term developed its modern meaning in reference to the constitution of the ancient Roman Republic, lasting from the overthrow of the kings in 509 BC to the establishment of the Empire in 27 BC. This constitution was characterized by a Senate composed of wealthy aristocrats wielding significant influence; several popular assemblies of all free citizens, possessing the power to elect magistrates and pass laws; and a series of magistracies with varying types of civil and political authority.

Most often a republic is a single sovereign state, but there are also sub-sovereign state entities that are referred to as republics, or that have governments that are described as republican in nature. For instance, the United States Constitution "guarantee[s] to every State in this Union a Republican form of Government". Another example was the Soviet Union, described by its undemocratic and extremely centralised government as being a federation of voluntarily united "Soviet socialist republics" with equal rights and ostensibly high degree of internal autonomy. The Russian Federation is similarly a state that is composed partly of several "republics".

Rhodesia (, ), officially from 1970 the Republic of Rhodesia, was an unrecognised state in Southern Africa from 1965 to 1979, equivalent in territory to modern Zimbabwe. Rhodesia was the de facto successor state to the British colony of Southern Rhodesia, which had been self-governing since achieving responsible government in 1923. A landlocked nation, Rhodesia was bordered by South Africa to the south, Bechuanaland (later Botswana) to the southwest, Zambia (formerly Northern Rhodesia) to the northwest, and Mozambique (a Portuguese province until 1975) to the east. From 1965 to 1979, Rhodesia was one of two independent states on the African continent governed by a white minority of European descent and culture, the other being South Africa.

In the late 19th century, the territory north of the Transvaal was chartered to the British South Africa Company, led by Cecil Rhodes. Rhodes and his Pioneer Column marched north in 1890, acquiring a huge block of territory that the company would rule until the early 1920s. In 1923, the company's charter was revoked, and Southern Rhodesia attained self-government and established a legislature. Between 1953 and 1963, Southern Rhodesia was joined with Northern Rhodesia and Nyasaland in the Federation of Rhodesia and Nyasaland.

The rapid decolonisation of Africa in the late 1950s and early 1960s alarmed a significant proportion of Southern Rhodesia's white population. In an effort to delay the transition to black majority rule, the predominantly white Southern Rhodesian government issued its own Unilateral Declaration of Independence (UDI) from the United Kingdom on 11 November 1965. The new nation, identified simply as Rhodesia, initially sought recognition as an autonomous realm within the Commonwealth of Nations, but reconstituted itself as a republic in 1970. Two African nationalist parties, the Zimbabwe African People's Union (ZAPU) and Zimbabwe African National Union (ZANU), launched an armed insurgency against the government upon UDI, sparking the Rhodesian Bush War. Growing war weariness, diplomatic pressure, and an extensive trade embargo imposed by the United Nations prompted Rhodesian prime minister Ian Smith to concede to majority rule in 1978. However, elections and a multiracial provisional government, with Smith succeeded by moderate Abel Muzorewa, failed to appease international critics or halt the war. By December 1979 Muzorewa had secured an agreement with ZAPU and ZANU, allowing Rhodesia to briefly revert to colonial status pending new elections under British supervision. ZANU secured an electoral victory in 1980, and the country achieved internationally recognised independence in April 1980 as Zimbabwe.

Rhodesia's largest cities were Salisbury (its capital city, now known as Harare) and Bulawayo. Prior to 1970, the unicameral Legislative Assembly was predominantly white, with a small number of seats reserved for black representatives. Following the declaration of a republic in 1970, this was replaced by a bicameral Parliament, with a House of Assembly and a Senate. The bicameral system was retained in Zimbabwe after 1980. Aside from its racial franchise, Rhodesia observed a fairly conventional Westminster system inherited from the United Kingdom, with a President acting as ceremonial head of state, while a Prime Minister headed the Cabinet as head of government.