In the sixteenth century, Europe was recovering from the Black Death and towns were growing and prospering again. Renewed interest in Greek thought and philosophy led some aristocrats to reconsider the works of Hero of Alexandria in hydraulics and pneumatics. His devices, such as temple doors operated by invisible weights or flowing liquids, and mechanical singing birds powered by steam, motivated several European princes to create similar clever devices to enhance their public image.
In Italy especially, some princes took things a stage further and constructed large water gardens incorporating mechanical devices in water settings. The best-known is the Villa d'Este at Tivoli, constructed in 1550 AD. A hill presented several fountains and dozens of grottoes, where water-driven figures moved or spouted water. Within 50 years there were imitations all over Europe; the best-known today is the Hellbrunn Palace, full of performing figures (human and animal), fountains that erupt without notice, and a water-powered puppet theater.