( Mental Floss ) -- Even in the midst of the Civil War, there was still one thing the North and South shared -- a serious addiction to caffeine.

Confederate troops were less likely to get a cup of coffee.

In that respect, the Union clearly had an advantage. Not only did the North have more than two-thirds of the population and control most of the heavy industry, railroads, and financial reserves in the country, it hoarded supplies of the highly addictive little bean, leaving the Confederacy to wage its own war against java deprivation.

Coffee: It's what's for breakfast, lunch and dinner

Throughout the Civil War, coffee was as prevalent on the battlefields as it is in offices today. In fact, the Union army was fueled by the stuff to the point that, if there was no time to boil water, the Boys in Blue would chew on whole beans as they marched. And at night, Union campsites were dotted with tiny fires, each boiling a pot of coffee like a million miniature Starbucks.

Beyond caffeine cravings, Union troops loved their coffee because it was, literally, the best thing on the menu.

Before the advent of helpful (and tasty!) artificial preservatives, a marching soldier's rations were neither varied nor particularly appetizing. Typically, they consisted of salted meat, unleavened bread (accurately christened "hardtack"), and a little sugar and salt.

It didn't help that Union supply chains were riddled with corrupt food contractors who charged the government top dollar for rotten, stale, and insect-ridden foodstuffs.

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Coffee, however, was almost always fresh because it was delivered in whole-bean form -- making it difficult for even the most dishonest supplier to skimp on quality. Not that they didn't try, of course. In fact, officials began requesting coffee as whole beans after some crooked contractors tried to up their per-pound profits by slipping sand and dirt into packages of ground coffee.

In 1861, hoping to cut down on the time soldiers spent roasting and grinding beans, the army switched to a concentrated proto-instant coffee. The new concoction, called "essence of coffee," was made by boiling prepared coffee, milk, and sugar into a thick gloop, which soldiers then reconstituted by mixing it with water.

The product reportedly tasted every bit as bad as you'd imagine, and thanks to the corrupt dairymen who sold the army spoiled milk, it also tended to cause diarrhea. Needless to say, the Union army was soon back on the bean.

Southern discomfort

Noxious as essence of coffee was, Confederate soldiers would have gladly downed a cup or two. But, because of a Union naval blockade, coffee (along with weapons, machinery, medicine, and other vital materials) was in short supply in the South.

Before the war, a pound of beans would have set you back around 20 cents in Yankee dough. Once pre-war stockpiles ran out, however, the same amount was running as high as $60 in Confederate money. (Despite the undervalued currency, that was still a lot.)

There was some coffee that made it into the Confederacy -- usually carried by steam-powered blockade-runner ships.

But, for the most part, Southerners had to rely on coffee substitutes, including various forms of roasted corn, rye, okra seeds, sweet potatoes, acorns, and peanuts. Unfortunately, all these imitations lacked potency, tasted awful, and upset the bowels.

The only slightly better alternative was tea made from the leaves of the native yaupon shrub. The good news was that it contained caffeine; the bad news was that it was incredibly difficult to digest.

Luckily, there was one surefire way for Southern folk to get their coffee -- by making peace with the Union. Soldiers on the front lines often called informal truces so Rebels could swap tobacco for Yankee coffee and then dash back to their camps before they were reported missing. E-mail to a friend

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