The first known European settler in Ozark was John Merrick Sr., a veteran of the Revolutionary War, in 1822. In honor of him, the town was named Merricks. It was later changed to Woodshop, which was its name when the town received its post office. The first appearance of the name Ozark was in 1855, when the citizens requested a name change.
The courthouse in Newton burned to the ground, and an election was made to find the new county seat. Ozark won, and in 1870 was incorporated.
According to the U.S. Census Bureau, the city has a total area of 34.5 square miles (89.3 km²), of which, 34.2 square miles (88.7 km²) of it is land and 0.2 square miles (0.6 km²) of it (0.70%) is water.
There were 6,126 households out of which 31.4% had children under the age of 18 living with them, 48.8% were married couples living together, 16.9% had a female householder with no husband present, and 30.9% were non-families. 27.7% of all households were made up of individuals and 10.6% had someone living alone who was 65 years of age or older. The average household size was 2.40 and the average family size was 2.92.
In the city the population was spread out with 24.9% under the age of 18, 8.5% from 18 to 24, 26.0% from 25 to 44, 24.7% from 45 to 64, and 15.9% who were 65 years of age or older. The median age was 39 years. For every 100 females there were 87.8 males. For every 100 females age 18 and over, there were 83.4 males.
The median income for a household in the city was $29,330, and the median income for a family was $38,633. Males had a median income of $30,236 versus $19,564 for females. The per capita income for the city was $15,984. About 14.8% of families and 19.0% of the population were below the poverty line, including 27.0% of those under age 18 and 18.0% of those age 65 or over.