Sejm of the Kingdom of Poland

The general sejm (Polish: sejm walny, also translated as the full or ordinary sejm) was the parliament of Kingdom of Poland. It had evolved from the earlier institution of wiec. It was one of the primary elements of the democratic governance in the Kingdom of Poland. The sejm was a powerful political institution, and from early 16th century, the Polish king could not pass laws without the approval of that body. The Sejm and the Seimas of the Grand Duchy of Lithuania was merged into the Sejm of the Polish–Lithuanian Commonwealth by the Union of Lublin in 1569.

Duration and frequencies of the sejms changed over time, with the six-week sejm session convened every two years being most common. Sejm locations changed throughout history. The number of sejm deputies and senators grew over time. Sejms have seen mostly majority voting.

The word sejm and sejmik are derived from old Czech sejmovat, which means "to bring together" or "to summon". In English, the terms general, full or ordinary sejm are used for the sejm walny.

There is no obvious date for the first sejm. Public participation in policy making in Poland can be traced to the Slavic assembly known as the wiec. Another form of public decision making was that of royal election, which occurred when there was no clear heir to the throne, or the heir's appointment had to be confirmed. There are legends of a 9th-century election of the legendary founder of the Piast dynasty, Piast the Wheelwright, and a similar election of his son, Siemowit (this would place a Polish ruler's election a century before an Icelandic one's by the Althing), but sources for that time come from the later centuries and their validity is disputed by scholars. The election privilege was usually limited to the most powerful nobles (magnates) or officials, and was heavily influenced by local traditions and strength of the ruler. By the 12th or 13th centuries, the wiec institution likewise limited its participation to high ranking nobles and officials. The nationwide gatherings of wiec officials in 1306 and 1310 can be seen as precursors of the general sejm.

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