German Valley, IL has a population of 486 and is the 19,710th largest city in the United States. The population density is 1,006 per sq mi which is 353% higher than the Illinois average and 1011% higher than the national average. The median age in German Valley is 42 which is approximately 12% higher than the Illinois average of 37. In German Valley, 71% of the population over 15 years of age are married, 98% speak English and 1% speak Spanish. 82% of German Valley residents were born in Illinois, 15% were born out of state, 0% were born outside of the United States and 2% were foreign born.