The area that would become Salt Lake County was settled in 1847 when the Mormon pioneers of the Church of Jesus Christ of Latter-day Saints (LDS Church), fleeing persecution in Eastern Europe arrived in the Salt Lake Valley after having traveled through the Emigration Canyon. Brigham Young, their leader, said: “This is the place” when he saw the valley, which at that time was a dry wasteland. However, it soon turned into a thriving self-sufficient community, through the Mormon pioneers extensive irrigation techniques. With Salt lake City as its base, thousands of Mormons from around the world would flock to the newly established area.

During the late 19th century, many mines were established, especially around Alta. Exploitation of mineral resources was difficult until the Utah Central Railroad arrived in 1870. Large deposits of copper and silver were found in a mine located in the Oquirrh Mountains called Bingam Canyon Mine. From the 20th century, most of the mines in the county have been closed. However, the Bingham Canyon mine kept growing, and today is one of the largest open pit mines in the world.

When the railroad arrived in the province, the population began to grow faster and non-Mormons began to settle in the city. As a result a population boom began and at the end of 1940, 1950 and 1960, the city of South Salt Lake, Murray, Midvale, and a lot of the eastern flank of the valley grew rapidly.

In 1960 the Salt Lake City Airport became international. Durng the 70′s and 80′s the growth of cities like Sandy, West Jordan, and what would become West Valley City has been phenomenal. Salt Lake county real estate began to pick up and within ten years, the whole area was transformed from farmland to bustling bedroom community of Salt Lake City. West Valley City was created by the merger of three different cities of Granger, Hunter, and Chesterfield in 1980.

In the 1990s, real estate shifted to the south and west. Former agricultural land and pastures became homes for sale. The cities of West Jordan, South Jordan, Riverton, Herriman and Draper are among the most prosperous cities in the state. The selection of Salt Lake City to host the Winter Olympics of 2002 triggered a construction boom in the city, which continued well after the Olympics left until the recession began in 2008. As the county’s population topped 1 million, one of the key issues in the county is urbanization. Only a few small rural areas remain at the west end of the valley.

The data show that the Mormon Church and the state of Utah, Salt Lake County was 53% Latter-day Saints (Mormons) in 2004, as the Salt Lake Tribune. extrapolated the figures correspond to 62% of Latter-day Saints in 1994 and 57% in 1999 and 2004 the percentage was 53%, makes the estimate that the Salt Lake County is very likely to be less than 50% of the LDS Today

The city of Bingham Canyon was completely destroyed and absorbed into the mine in 1972, and the dismantling of the lark in 1980 completed the process. The only city left in mining Copperton County, located southwest of West Jordan, with about 800 inhabitants.