During the Civil War, Union General George B. McClellan issued the very unpopular General Order #136, which banned the issuance of whiskey among the Federal troops. Whiskey was thought to increase bravery, or at least bravado, but it also caused lethargy, indolence, sluggishness and not a little insubordination. Thus, the drink of choice for soldiers in the field became coffee. And a little caffeine made them more alert! And being alert, attentive and on the ball is what a general wants in a soldier.
In 1861, the standard daily ration of victuals in the Union army was based on the assumption that not all required ingredients would be available at all times and places. Supplies were issued on an either-or basis. Each 100-man company was to share ten pounds of roasted coffee or one and a half pounds of tea. The Confederate War Department adopted precisely the same ration allowance as the old prewar United States, except that the Confederacy recognized the scarcity of coffee and cut rations from ten pounds of coffee to six. In any event the Southern commissary was rarely able to provide coffee. The blockades were cutting off the importation of everything from New York apples to Brazilian coffee. In 1863, responding to the rigors of campaigning, even the Union War Department revised the ration from ten pounds of roasted coffee beans to ten pounds of green coffee beans or eight pounds of roasted beans. Because of an average twenty percent moisture loss in roasting, ten pounds of green equals eight pounds of roasted coffee.
Soldiers North and South could go for days without food as long as they had their coffee. In the Confederacy, coffee became as highly prized as shoes, and commanded outrageous prices in times of insufficiency. Substitutes were tried using burnt chicory or parched corn. Some used the roasted dry crusts of brown bread, others tried rye grain soaked in rum, if they could get rum, and even others attempted to roast peas in the same way as coffee. Even acorns were roasted and ground. Nothing approached the real article. As a result, coffee was the item most often asked for when Rebs informally met Yanks between the lines for illicit trading. Virginia tobacco was most often the commodity exchanged. The taste of coffee laced with burnt chicory became habitual, perhaps a sign of Southern pride, and you can buy coffee laced with chicory in Louisiana to this very day.
There was rarely any shortage of coffee beans in the North, and coffee became so popular with the army that the Sharps Rifle Manufacturing Company issued a few experimental models of their New Model 1863 Carbine with a small coffee mill with a detachable handle in the stock! It has been said that the idea was to issue one Sharps carbine with a coffee grinder built into the butt stock per 100-man Company. According to research by David H. Arnold, the grinder might have been a mill for grinding forage grains into flour. It is reported that perhaps only four are now in existence.
According to the Civil War Cookbook, the best coffee was slow roasted over a low fire, "until of a chestnut brown color and not burnt, as is so commonly done." It was to be boiled briskly for two minutes, then taken from the fire at once, a little cold water thrown in, then the boiler's contents poured through a piece of flannel after it had settled for five minutes."