Question: Which general region of Idaho was originally settled by members of The Church of Jesus Christ of Latter-day Saints?

Context paragraphs:
Mormon Corridor: The Mormon Corridor is the area of Western North America that were settled between 1850 and approximately 1890 by members of The Church of Jesus Christ of Latter-day Saints (LDS Church), who are commonly known as Mormons.

Temple (Latter Day Saints): In the Latter Day Saint movement, a temple is a building dedicated to be a house of God and is reserved for special forms of worship.  A temple differs from a church meetinghouse, which is used for weekly worship services.  Temples have been a significant part of the Latter Day Saint movement since early in its inception.  Today, temples are operated by several Latter Day Saint denominations.  The most prolific builder of temples of the Latter Day Saint movement is The Church of Jesus Christ of Latter-day Saints (LDS Church).  There are 157 operating temples (which includes 2 previously dedicated, but closed for renovation), 12 under construction, and 13 announced (not yet under construction).  Several other variations of the church have built or attempted to build temples.  The Community of Christ operates two temples in the United States, which are open to the public and are used for worship services, performances, and religious education.  Other denominations with temples are the Apostolic United Brethren, the Church of Christ, the Fundamentalist Church of Jesus Christ of Latter-Day Saints and the Righteous Branch of the Church of Jesus Christ of Latter-day Saints.

Affirmation: Gay &amp; Lesbian Mormons: Affirmation: LGBT Mormons, Families & Friends is an international organization for individuals who identify as gay, lesbian, transgender, bisexual, queer, intersex, or same-sex attracted, and their family members, friends, and church leaders who are members or former members of The Church of Jesus Christ of Latter-day Saints (LDS or Mormon Church).  According to its charter, Affirmation "offers its members strength and support in solving personal problems through mutual acceptance and fellowship" and "work[s] for the understanding and acceptance of gays and lesbians as full, equal and worthy persons within the Church of Jesus Christ of Latter-day Saints and society, and to help them realize and affirm self-worth."

First Presidency: Among many churches in the Latter Day Saint movement, the First Presidency (also known as the Quorum of the Presidency of the Church) is the highest presiding or governing body.  Present-day denominations of the movement led by a First Presidency include The Church of Jesus Christ of Latter-day Saints (LDS Church), the Community of Christ, Remnant Church of Jesus Christ of Latter Day Saints.  and the Righteous Branch of the Church of Jesus Christ of Latter-Day Saints.

Children's Songbook: The Children's Songbook of The Church of Jesus Christ of Latter-day Saints is the official songbook for children in The Church of Jesus Christ of Latter-day Saints (LDS Church).  It was first published in English in 1989.  These songs are for the Primary, which is an organization in the LDS Church for children between the ages of 18 months and 12 years old, who learn about the teachings of Jesus Christ.

Latter-day Saint Biographical Encyclopedia: Latter-day Saint Biographical Encyclopedia: A Compilation of Biographical Sketches of Prominent Men and Women in the Church of Jesus Christ of Latter-day Saints (abbreviated LDS Biographical Encyclopedia) is a four-volume biographical dictionary by Andrew Jenson that includes a church chronology and biographical information about leaders and other prominent members of The Church of Jesus Christ of Latter-day Saints (LDS Church) from its founding in 1830 until 1930.

Eastern Idaho: Eastern Idaho is the area of Idaho lying east of the Magic Valley region.  It is generally understood to include: Bannock, Bear Lake, Bingham, Bonneville, Butte, Caribou, Clark, Custer, Franklin, Fremont, Jefferson, Madison, Oneida, Power and Teton Counties.  In terms of culture much of the region is in the Mormon Corridor and The Church of Jesus Christ of Latter-day Saints plays a major role in the lives of a majority of the region's residents.

History of the Church (Joseph Smith): History of the Church (cited as HC) (originally entitled History of Joseph Smith; first published under the title History of the Church of Jesus Christ of Latter-day Saints; nicknamed Documentary History of the Church or DHC) is a semi-official history of the early Latter Day Saint movement during the lifetime of founder Joseph Smith.  It is largely composed of Smith's writings and interpolations and editorial comments by Smith's secretaries, scribes, and after Smith's death, historians of The Church of Jesus Christ of Latter-day Saints (LDS Church).  The history was written between 1839 and 1856 .  Part of it was published in "Times and Seasons" and other church periodicals.  It was later published in its entirety with extensive annotations and edits by B. H. Roberts as part of a seven-volume series beginning in 1902 as "History of the Church of Jesus Christ of Latter-day Saints".

Latter Day Saint movement: The Latter Day Saint movement (also called the LDS movement, LDS restorationist movement, or Smith–Rigdon movement) is the collection of independent church groups that trace their origins to a Christian primitivist movement founded by Joseph Smith in the late 1820s.  Collectively, these churches have over 15 million members.  The vast majority of adherents belong to The Church of Jesus Christ of Latter-day Saints (LDS Church), with their predominant theology being Mormonism.  The LDS Church self-identifies as Christian.  A minority of Latter Day Saint adherents, such as members of the Community of Christ, believe in traditional Protestant theology, and have distanced themselves from some of the distinctive doctrines of Mormonism.  Other groups include the Remnant Church of Jesus Christ of Latter Day Saints, which supports lineal succession of leadership from Smith's descendants, and the more controversial Fundamentalist Church of Jesus Christ of Latter-Day Saints, which defends the practice of polygamy.

Thomas B. Marsh: Thomas Baldwin Marsh (November 1, 1800 – January 1866) was an early leader in the Latter-day Saint movement and an original member of the Quorum of the Twelve Apostles.  He served as the first President of the Quorum of the Twelve Apostles of the Church of Jesus Christ of Latter-day Saints from 1835 to 1839.  He was excommunicated from the church in 1839, and remained disaffected for almost 18 years.  Marsh was rebaptized into The Church of Jesus Christ of Latter-day Saints (LDS Church) in July 1857, but never again served in church leadership positions.

Supporting paragraphs: Eastern Idaho Mormon Corridor
Answer: Eastern Idaho