[4] After World War I and due to significant popular demand, Johann II granted a new constitution, which was ratified on 5 October 1921.

In 1867, Alexander II of Russia had offered Johann the purchase of Russian Alaska, but he refused as he believed the territory was useless.

[9] Johann II, an outstanding art connoisseur and a generous patron, added much to the Liechtenstein Princely Collections.

It was not until the German occupation of the Czech lands at the beginning of World War II that the residence was moved to Vaduz.

As Johann entered his later years, his eyesight began to decline rapidly and on 12 November 1928, he underwent surgery to remove cataracts.