20th century research and practice of science led to advancement in the fields of communication, engineering, travel, medicine, and war. 20th century The 20th (twentieth) century was a century that began on January 1, 1901 and ended on December 31, 2000. It was the tenth and final century of the 2nd millennium. It is distinct from the century known as the 1900s which began on January 1, 1900 and ended on December 31, 1999. The 20th century was dominated by a chain of events that heralded significant changes in world history as to redefine the era: flu pandemic, World War I and
Catholic Church in the 20th century stated: "The second millennium of Christian history began with a painful wounding of the unity of the Church; the end of this millennium has seen a real commitment to restoring Christian unity." Pope John Paul II visited other strongly Orthodox areas such as Ukraine, despite lack of welcome at times. He said that healing the divisions between Western and Eastern Christianity was one of his fondest wishes. Catholic Church in the 20th century The Roman Catholic Church in the 20th century had to respond to the challenge of increasing secularization of Western society and persecution resulting from great social unrest