On research sweet tea has an interesting history:
The Origins of Sweet Tea
In 1795 Andre Michaux, French explorer and botanist, introduced a variety of plants to the fields of South Carolina, including gardenias, azaleas, camellias and green tea, in hopes that the exotic flora would appeal to wealthy plantation owners. In Charleston, S.C. he grew the first crop of tea in the United States.
At the beginning of the nineteenth century, recipes for cold teas were popularized in both Britain and America. These brews, referred to as punches, were commonly made from green tea spiked with alcohol.
There are many speculations as to why sweet tea became a Southern classic. At the end of the Civil War, many Southerners experienced poverty. Sweet tea – requiring only water, tea leaves and sugar – was not only cheap, but also readily available as the majority of cane crops were grown in the South.
Historians have a third theory. The conservative branch of Christianity that dominated the South frowned upon wine, beers and liquor. Sweet tea then became a common replacement for alcoholic beverages, and its consumption spread rapidly during the era of Prohibition.
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