During the 1820s intense religious and social movements spread across the country calling alcohol and drunkenness a "national curse." They were called temperance movements. The first state to have a temperance law was Massachusetts who in 1838 enacted a law prohibiting the sale of liquor in less than 15 US gallons (57 l; 12 imp gal) quantities. In 1846, Maine passed the first state prohibition law. It was repealed two years later, still, other states also passed similar laws.
The prohibition laws had many loopholes (ways to get around the law) that were quickly taken advantage of. The biggest loophole was that neither the Eighteenth Amendment nor the Volstead Act made it illegal to drink or be drunk in public. Farmers who grew fruit quickly learned to sell their harvests in dehydrated bricks. The warning label included instructions on how to easily turn the bricks into alcoholic drinks. Pharmacists were allowed to prescribe whiskey for any number of ailments from anxiety to the flu. As bootleggers learned of this, the number of pharmacies tripled in places like New York state. Tools and ingredients to make alcohol at home were sold in hardware and grocery stores. Books on how to make liquor were also legal.
Eighteenth Amendment to the United States Constitution Facts for Kids. Kiddle Encyclopedia.