Jehovah's Witnesses originated as a branch of the Bible Student movement, which developed in the United States in the 1870s among followers of Christian restorationist minister Charles Taze Russell. Bible Student missionaries were sent to England in 1881 and the first overseas branch was opened in London in 1900. The group took on the name International Bible Students Association and by 1914 it was also active in Canada, Germany, Australia and other countries. The movement split into several rival organizations after Russell's death in 1916, with one—led by Joseph "Judge" Rutherford—retaining control of The Watch Tower and the Watch Tower Bible and Tract Society of Pennsylvania. Under Rutherford's direction, the International Bible Students Association introduced significant doctrinal changes that resulted in many long-term members leaving the organization. The group regrew rapidly, particularly in the mid-1930s with the introduction of new preaching methods. In 1931, the name Jehovah's witnesses was adopted, further cutting ties with Russell's earlier followers. Substantial organizational changes continued as congregations and teaching programs worldwide came under centralized control. Further changes of its doctrines led to the prohibition of blood transfusions by members, abandonment of the cross in worship, rejection of Christmas and birthday celebrations and the view of the biblical Armageddon as a global war by God that will destroy the wicked and restore peace on earth. In 1945, the Watch Tower Society, which Russell had founded as a publishing house, amended its charter to state that its purposes included preaching about God's Kingdom, acting as a servant and governing agency of Jehovah's Witnesses and sending out missionaries and teachers for the public worship of God and Jesus. The denomination was banned in Canada in World War I, and in Germany, the Soviet Union, Canada and Australia during World War II. Members suffered widespread persecution and mob violence in some of those countries and in the United States. The group initiated dozens of high-profile legal actions in the United States and Canada between 1938 and 1955 to establish the right of members to sell literature from door to door, abstain from flag salute ceremonies and gain legal recognition as wartime conscientious objectors. Members of the denomination suffered persecution in some African countries in the 1960s and 1970s. Since 2004 the group has suffered a series of official bans in Russia. 1869–1916 Adventist influences About 1869 17-year-old Russell attended a meeting in Pittsburgh, Pennsylvania of a group he