The Watchtower in the context of Watch Tower Bible and Tract Society of Pennsylvania

Jehovah's Witnesses is a nontrinitarian, millenarian, and restorationist Christian denomination, stemming from the Bible Student movement founded by Charles Taze Russell in the nineteenth century. Russell co-founded Zion's Watch Tower Tract Society in 1881 to organize and print the movement's publications. A leadership dispute after Russell's death resulted in several groups breaking away, with Joseph Franklin Rutherford retaining control of the Watch Tower Society and its properties. Rutherford made significant organizational and doctrinal changes, including adoption of the name Jehovah's witnesses in 1931 to distinguish the group from other Bible Student groups and symbolize a break with the legacy of Russell's traditions. In 2024, Jehovah's Witnesses reported a peak membership of approximately 9 million worldwide.

Jehovah's Witnesses are known for their evangelism, distributing literature such as The Watchtower and Awake!, and for refusing military service and blood transfusions. They consider the use of God's name vital for proper worship. They reject Trinitarianism, inherent immortality of the soul, and hellfire, which they consider unscriptural doctrines. Jehovah's Witnesses believe that the destruction of the present world system at Armageddon is imminent, and the establishment of God's kingdom over earth is the only solution to all of humanity's problems. They do not observe Christmas, Easter, birthdays, or other holidays and customs they consider to have pagan origins incompatible with Christianity. They prefer to use their own Bible translation, the New World Translation of the Holy Scriptures.

Charles Taze Russell (February 16, 1852 – October 31, 1916), or Pastor Russell, was an American Adventist minister from Pittsburgh, Pennsylvania, and founder of the Bible Student movement. He was an early Christian Zionist.

In July 1879, Russell began publishing a monthly religious magazine, Zion's Watch Tower and Herald of Christ's Presence. In 1881, he co-founded Zion's Watch Tower Tract Society with William Henry Conley as president. In 1884 the corporation was registered, with Russell as president. Russell wrote many articles, books, tracts, pamphlets and sermons, totaling approximately 50,000 pages. From 1886 to 1904, he published a six-volume Bible study series titled Millennial Dawn, later renamed Studies in the Scriptures, nearly 20 million copies of which were printed and distributed around the world in several languages during his lifetime. (A seventh volume was commissioned by his successor as society president, Joseph Rutherford, and published in 1917.) The Watch Tower Society ceased publication of Russell's writings in 1927, though his books are still published by several independent groups.

Awake! is an illustrated religious magazine published by the Watch Tower Bible and Tract Society of Pennsylvania. It is considered to be a companion magazine of The Watchtower, and is distributed by Jehovah's Witnesses. The Watch Tower Society reports a worldwide circulation of about 33.206 million copies per issue in 270 languages.

The doctrines of Jehovah's Witnesses have developed since the publication of The Watchtower magazine began in 1879. Early doctrines were based on interpretations of the Bible by Watch Tower Bible & Tract Society founder Charles Taze Russell, then added to, altered, or discarded by his successors, Joseph Rutherford and Nathan Knorr. Since 1976, doctrinal changes have been made at closed meetings of the group's Governing Body, whose decisions are described as "God's progressive revelations".These teachings are disseminated through The Watchtower, and at conventions and congregation meetings. Most members of the denomination outside the Governing Body play no role in the development of doctrines and are expected to adhere to all those decided at the Warwick, NY headquarters. Jehovah's Witnesses are taught to welcome doctrinal changes, regarding such "adjustments" as "new light" or "new understanding" from God and proving that they are on the "path of the righteous".