No, Neuschwanstein Castle was not built by slaves. In fact, it was quite the opposite; the construction of the castle in the late 19th century was a massive economic driver for the local region, providing well-paid jobs for hundreds of skilled craftsmen, stonemasons, and laborers. King Ludwig II of Bavaria, who commissioned the castle as a personal retreat and a monument to Richard Wagner, was known for his perfectionism and his commitment to modern construction techniques. He insisted on the use of advanced technology, such as a steam-powered crane and a complex heating system, which required highly trained professionals rather than forced labor. However, the project was financially disastrous for the King himself; he used his own personal fortune (and significant borrowed funds) rather than state money to build it, leading to his eventual deposition and mysterious death. The castle was never fully completed, and ironically, it was opened to the public as a tourist attraction just six weeks after the King's death in 1886.