HOW MUCH WILL YOUR WEBSITE COST?

Prior to the arrival of the first European settlers, the St. George area was inhabited by the Virgin River Anasazi and later by the Southern Paiute tribe. The first Europeans in the area were part of the Domínguez–Escalante expedition in 1776.

St. George was founded as a cotton mission in 1861 under the direction of Apostle Erastus Snow. It was called Dixie by Brigham Young, who was president of The Church of Jesus Christ of Latter-day Saints (LDS Church). While early settlers cultivated cotton as a commodity crop, they did not succeed in producing it at competitive market rates; consequently, cotton farming was eventually abandoned. More important to the economy was tourism, which developed as the railroads began to carry visitors to the nearby Zion National Park.

At the outbreak of the American Civil War in 1861, Young organized the settlement of what is now Washington County.

The settlement was named after George A. Smith, an LDS Church apostle.

In April 1877, the LDS Church completed the St. George Utah Temple. It is the church's third and oldest continually-operating temple in the world. (The temple has been closed since November 2019 for renovation.)

The 1992 St. George earthquake destroyed three houses as well as above- and below-ground utilities, causing about US$1 million in damage.

St. George was the location of the 1997 United States Academic Decathlon national finals.

In January 2005, a 100-year flood occurred throughout the region, due to prolonged heavy rainfall overflowing the Virgin River and Santa Clara River. One person was killed and 28 homes were destroyed by the Santa Clara River.

In the early 1950s, St. George received the brunt of the fallout of above-ground nuclear testing at the Yucca Flats/Nevada Test Site northwest of Las Vegas. Winds routinely carried the fallout of these tests directly through the St. George and southern Utah area. Marked increases in the frequency of cancer in the population, not limited to leukemia, lymphoma, thyroid cancer, breast cancer, melanoma, bone cancer, brain tumors, and gastrointestinal tract cancers, were reported from the mid-1950s until the early 1980s. It is believed that much of the cast and crew of The Conqueror contracted cancer because of this.

A 1962 United States Atomic Energy Commission report found children living in St. George, Utah, at the time of the fallout may have received doses to the thyroid of radioiodine as high as 120 to 440 rads" (1.2 to 4.4 Gy).

As of 2015 the largest self-reported ancestry groups in St. George, Utah are:

In 2018, the city's population was estimated at 87,178. St. George was declared the fourth fastest-growing metropolitan area in the United States in 2018.

As of 2018, there were 27,552 households. The population density was 1,135 people per square mile. As of 2010, there were 32,089 housing units at an average density of per square mile. The city's racial makeup was 87.2% White, 0.7% African-American, 1.5% Native American, 0.8% Asian, 1.0% Pacific Islander, and 8.9% from other races. 12.8% of the population was Hispanic or Latino of any race.

As of the 2000 census, there were 17,367 households, out of which 34.2% had children under the age of 18 living with them, 63.6% were married couples living together, 8.6% had a female householder with no husband present, and 24.9% were non-families. 19.4% of all households were made up of individuals, and 10.2% had someone living alone who was 65 years old or older. The average household size was 2.81 individuals and the average family size was 3.21.

In the city, the age distribution of the population showed 28.4% under the age of 18, 13.7% from 18 to 24, 22.0% from 25 to 44, 16.8% from 45 to 64, and 19.3% who were 65 years of age or older. The median age was 31 years. For every 100 females, there were 94.5 males. For every 100 females age 18 and over, there were 91.2 males.

The median income for a household in the city was $36,505, and the median income for a family was $41,788. Males had a median income of $31,106 versus $20,861 for females. The per capita income for the city was $17,022. About 7.4% of families and 11.6% of the population were below the poverty line, including 14.4% of those under age 18 and 4.4% of those age 65 or over. A significant portion of the over 65 population was "snowbirds", who live in St. George during the winter.

Approximately 78.0% of St. George's residents identify as religious; below are stats as of 2014: