President of the Quorum of the Twelve Apostles (LDS Church)

President of the Quorum of the Twelve Apostles is a priesthood calling in The Church of Jesus Christ of Latter-day Saints (LDS Church). In general, the President of the Quorum of the Twelve is the most senior apostle in the church, aside from the President of the Church. When the President of the Church dies, it is the President of the Quorum of the Twelve who becomes the new church president. The calling of President of the Twelve has been held by 26 men (one of whom served two non-consecutive terms), 15 of whom have gone on to become President of the Church. The current President of the Quorum of the Twelve is Russell M. Nelson.

Upon the death of the President of the Church, the First Presidency automatically dissolves, leaving the Twelve Apostles as the highest leadership body and their President as the highest official in the church. On the death of church president Joseph Smith in 1844, this position was held by Brigham Young, and he persuaded the majority of church members that Smith's death left him and not Sidney Rigdon, who had been Smith's First Counselor in the First Presidency, as the senior leader. Smith had reportedly taught the apostles, "Where I am not, there is no First Presidency over the Twelve."

In 1847, the Quorum of the Twelve reconstituted the First Presidency, with Brigham Young as church president. During Young's presidency, seniority within the Quorum of the Twelve was formalized to mean "continuous service as an Apostle since being ordained as one of the Twelve". The original apostles of 1835 had been ranked by age, and two of them had been excommunicated and later restored to fellowship. With this rule in place, it was John Taylor who led the church after Young's death in 1877, first as President of the Twelve and after 1880 as President of the Church with Wilford Woodruff as President of the Twelve.

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