Voivodes of the Polish–Lithuanian Commonwealth were one of the highest ranking officials who could sit in the Senate of Poland.
The title merged with the Polish Voivode or Wojewoda (Slavic Woi-woda/вои-вода (Cyrillic), with two functions, in army or war, and as a “guide” or director, a lexical and institutional equivalent of the Latin Dux Exercituum and Duke, known by the German Herzog, each meaning "leader of the army").
The powers of voivodes varied, as determined by historical precedent specific to each voivodeship.
Administrative powers were limited to the role of Marshal of the Sejmik, but even that had disappeared by the time of the Commonwealth.
The exceptions to this rule were the voivodes of Połock and Vilnius, who were elected by the szlachta (nobility) from their respective lands (although they still had to be approved by the King).
Even when a voivodeship ceased to exist after borders shifted, the office remained intact and the voivode preserved his privileges, such as the right to sit and vote in the Senate.
They took their seats after the bishops, as the first secular officials, although in practice their power was less than that of Ministers of the Polish-Lithuanian Commonwealth (who however sat last in the Senate).