American Commonwealths

Commonwealth is a traditional English term for a political community founded for the common good. Historically it has sometimes been synonymous with "republic".

The noun "commonwealth", meaning "public welfare general good or advantage" dates from the 15th century. Originally a phrase (the common-wealth or the common weal – echoed in the modern synonym "public weal") it comes from the old meaning of "wealth", which is "well-being", and is itself a loose translation of the Latin res publica (republic). The term literally meant "common well-being". In the 17th century, the definition of "commonwealth" expanded from its original sense of "public welfare" or "commonweal" to mean "a state in which the supreme power is vested in the people; a republic or democratic state". "Better things were done, and better managed ... under a Commonwealth than under a King." Pepys, Diary (1667)

The term evolved to become a title to a number of political entities. Three countries – Australia, the Bahamas, and Dominica – have the official title "Commonwealth", as do four U.S. states and two U.S. territories. More recently, the term has been used to name some fraternal associations of nations, most notably the Commonwealth of Nations, an organization primarily of former territories of the British Empire, which is often referred to as simply "the Commonwealth".

Translations of Roman writers' works to English have on occasion translated "Res publica", and variants thereof, to "the commonwealth", a term referring to the Roman state as a whole.

The Commonwealth of England was the official name of the political unit (de facto military rule in the name of parliamentary supremacy) that replaced the Kingdom of England (after the English Civil War) from 1649–53 and 1659–60, under the rule of Oliver Cromwell and his son and successor Richard. From 1653 to 1659, although still legally known as a Commonwealth, the republic, united with the former Kingdom of Scotland, operated under different institutions (at times as a de facto monarchy) and is known by historians as the Protectorate. In a British context, it is sometimes referred to as the "Old Commonwealth".

...
Wikipedia