His full name – just one of his many unique characteristics – was Nephi United States Centennial Jensen, in honor of the centennial anniversary of the American Declaration of Independence (he was born on 16 February 1876). He was the son of Loren and Christine Jensen, converts to the Church of Jesus Christ of Latter-day Saints (LDS) who immigrated to Utah’s Salt Lake Valley from the Netherlands in 1861. He grew up in what became Salt Lake County, attending grade school in Sugar House, until his senior year in high school, when the family moved to Montezuma County, Colorado. Shortly after graduating high school, he began his obligatory mission work, at which he excelled.

  
Elder Jensen's role in the establishment of an unexpectedly successful community of Latter-day Saints in South Georgia seems appropriate, though no less impressive, given an understanding of his personality, worldview, and talents. He was a dynamic character who later became something of a celebrity in the LDS Church.

He was set apart and called in February 1898 to serve a mission to the Southern States (SSM), where he was assigned to labor in its Florida Conference, which then included Florida, South Georgia, and parts of Alabama. He also served as clerk for the conference until he was released from his work in July 1900. Upon returning home, Jensen wasted no time in pursuing a family and career. On 9 April 1902, he married Margaret Smith, daughter of Jesse Nathaniel Smith, Sr., a pioneer Latter-day Saint and cousin of the prophet, Joseph Smith. He enrolled in classes at the Latter-day Saints College (now Brigham Young University), and later at the University of Utah, where he studied law. In February 1906, he was admitted to the state bar of the Supreme Court of Utah. That November, he was elected to the state legislature, where he served one term.

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