This is the story of an upward slopping demand curve in the absence of information, and one of my favourite anecdotes from childhood:
Ioannis Kapodistrias (in Greek Ιωάννης Καποδίστριας, in Italian Giovanni Capo d'Istria, Conte Capo d'Istria) (February 11, 1776 – October 9, 1831) was a Greek diplomat of the Russian Empire and later first head of state of independent Greece.
On his arrival [to Greece], Kapodistrias launched a major reform and modernisation programme that covered all areas. He re-established military unity, bringing an end to the second phase of the civil war; re-organised the military, which was then able to reconquer territory lost to the Ottoman military during the civil wars; introduced the first modern quarantine system in Greece, which brought epidemics like typhoid fever, cholera and dysentery under control for the first time since the start of the War of Independence; negotiated with the Great Powers and the Ottoman Empire the borders and the degree of independence of the Greek state and signed the peace treaty that ended the War of Independence with the Ottomans; introduced the phoenix, the first modern Greek currency; organised local administration; and, in an effort to raise the living standards of the population, introduced the cultivation of the potato into Greece.
The way Kapodistrias introduced the cultivation of the potato remains famously anecdotal today. Having ordered a shipment of potatoes, at first he ordered that they should be offered to anyone who would be interested. However the potatoes were met with indifference by the population and the whole scheme seemed to be failing. Therefore Kapodistrias, knowing of the contemporary Greek attitudes, ordered that the whole shipment of potatoes be unloaded in public display on the docks of Nafplion, and placed severe-looking guards guarding it. Soon, rumours circulated that for the potatoes to be so well guarded they had to be of great importance. People would gather to look at the so-important potatoes and soon some tried to steal them. The guards had been ordered in advance to turn a blind eye to such behaviour, and soon the potatoes had all been "stolen" and Kapodistrias's plan to introduce them to Greece had succeeded.