A petition for incorporation was filed in District Court on June 11, 1872 with an election subsequently held in which there were 46 votes in favor and 16 votes against.
The completion of the Chicago, Burlington, and Quincy Railroad Line through Pleasantville in 1879 caused an increase in development and Pleasantville became one of the active business centers in Marion County and the principal shipping point between Knoxville and Des Moines.
The earliest population figures available begin in 1900 with 738 residents.
The first school was built in the fall of 1847, and in 1868, the school district joined with the Masonic Lodge in building a three story brick building that remained a school facility until 1992. Today, the Pleasantville School district consists of three buildings, an elementary, a middle school, and a high school.
There were 615 households out of which 34.5% had children under the age of 18 living with them, 50.9% were married couples living together, 10.2% had a female householder with no husband present, and 35.8% were non-families. 32.2% of all households were made up of individuals and 15.8% had someone living alone who was 65 years of age or older. The average household size was 2.44 and the average family size was 3.11.
In the city the population was spread out with 29.1% under the age of 18, 6.0% from 18 to 24, 28.6% from 25 to 44, 20.0% from 45 to 64, and 16.3% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 92.6 males. For every 100 females age 18 and over, there were 83.4 males.
The median income for a household in the city was $40,000, and the median income for a family was $48,295. Males had a median income of $35,551 versus $25,948 for females. The per capita income for the city was $18,279. About 3.8% of families and 7.1% of the population were below the poverty line, including 4.5% of those under age 18 and 20.0% of those age 65 or over.