When his father, Prince Josef Johann Adam died, Johann Nepomuk Karl (born in 1724, died in 1748) was only 8 years old and grew under the tutelage of his uncle, Prince Josef Wenzel, who also handled the principal governmental tasks for him.
Johann Nepomuk Karl could dedicate himself only for a short period of time to the state affairs, because three years after he was of age he died, without leaving any male descendants.
With him the line of Prince Anton Florian, the real originator of the
House of Liechtenstein, also died out already in the second generation,
and the government passed over to Prince Josef