King Frederick II of Prussia introduced potatoes to Prussia in the 18th century to diversify their food supply beyond just wheat. Since potatoes were an unfamiliar vegetable, the king had to use creative marketing tactics to encourage the Prussian people to grow and eat them. He planted a royal potato garden with around-the-clock guards to pique people's curiosity. When the guards were not watching at night, townspeople began stealing the potatoes. This led more Prussians to plant their own potato crops, ensuring food security and popularizing the vegetable. Through persistence and innovative promotion, Frederick was ultimately able to change perceptions and introduce a new food source to his kingdom.