Vienna is a city located in Johnson County Illinois. It is also the county seat of Johnson County. With a 2020 population of 1,438, it is the 554th largest city in Illinois and the 8881st largest city in the United States . Vienna is currently declining at a rate of -0.07% annually but its population has increased by 0.28% since the most recent census, which recorded a population of 1,434 in 2010. Vienna reached it's highest population of in . Spanning over 3 miles, Vienna has a population density of 507 people per square mile.
The average household income in Vienna is $51,661 with a poverty rate of 23.87%. The median rental costs in recent years comes to $502 per month, and the median house value is $79,100. The median age in Vienna is 45.8 years, 45.2 years for males, and 49.2 years for females.