The adherents of this Baltic religion prospered relatively unhindered until the 9th century when they began to come under pressure from outside Christian forces. The Annals of Quedlinburg mention a missionary, Bruno of Querfurt, who was killed along with 18 men by Yotvingians while attempting to convert the pagans in the area of Lithuania and Prussia in 1009 CE. This was the first time the name of Lithuania was mentioned in written sources. Other sources suggest Bruno had been killed for violating The Holy Forest and destroying statues of gods.