How many citizens were in the holy roman empire?

The population of the Holy Roman Empire varied significantly over time and by region, but estimates suggest it was around 15 to 20 million people during its peak in the late medieval period. The empire encompassed a diverse range of territories, including modern-day Germany, Austria, Switzerland, and parts of Italy and France. Due to its complex political structure, there was no single citizenship; instead, individuals were subjects of various princes, electors, and other local rulers within the empire.