Bull of Gniezno

Ex commisso nobis, more commonly known as the Bull of Gniezno, was a papal bull issued on July 7, 1136 by Pope Innocent II. The bull split off the Bishopric of Gniezno from the Archbishop of Magdeburg. From a historical perspective, the bull is especially important as it contains the earliest written record of the Polish language. Slavic language scholar Aleksander Brückner called the document a "złota bulla języka polskiego" (the golden bull of the Polish language).

The election of Pope Innocent II in 1130 prompted a schism in the Roman Catholic Church. The Polish church supported the appointment of the Antipope Anacletus II, while Saint Norbert of Xanten, Archbishop of Magdeburg, remained faithful to Innocent. In Norbert's last years, he was chancellor and adviser to Lothair II, the Holy Roman Emperor, and persuaded him to lead an army to Rome to restore Innocent to the papacy in 1133.

Following Norbert's death, Lothair pressured Innocent to issue an order rejecting the independence and authority of the Archbishop of Gniezno, and affirming the Archbishop of Magdeburg's authority over the Archdiocese of Gniezno and, by default, the entirety of the Polish church. As a result, the Polish prelates swore fealty to the Antipope.

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