Bruno of Querfurt

Bruno of Querfurt, O.S.B. Cam. (German: Brun von Querfurt; c. 974 – 14 February or 9 March 1009), also known as Brun, was a Christian missionary, bishop, Camaldolese monk and martyr. He was active in the eastern regions of the Holy Roman Empire and became one of the leading figures in the early Christian missions to the peoples of northeastern Europe. Bruno was killed in Prussia, near the frontier of Kyivan Rus' and Lithuania, while attempting to convert the Old Prussians to Christianity. He is venerated as the "Second Apostle of the Prussians".

Bruno was educated at the cathedral school of Magdeburg and entered the service of the imperial court. He later joined the monastic community of Avellanese hermits under Saint Romuald, becoming part of the early Camaldolese movement. His spiritual formation combined Western monastic discipline with eremitical traditions, shaping the missionary zeal that defined his later career.