Polish–Lithuanian Commonwealth

Aristocratic republic in Europe (1569–1795)

The Polish–Lithuanian Commonwealth, also referred to as Poland–Lithuania or the First Polish Republic (Polish: I Rzeczpospolita), was a federative real union between the Kingdom of Poland and the Grand Duchy of Lithuania, existing from 1569 to 1795. This state was among the largest, most populated countries of 16th- to 18th-century Europe. At its peak in the early 17th century, the Commonwealth spanned approximately 1,000,000 km² (390,000 sq mi) and supported a multi-ethnic population of around 12 million as of 1618.

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