As you can imagine in a battle between tens of thousands of men, things can get confusing. It even becomes difficult to know which soldier is on which side. The main way to tell the difference is by the uniforms.
US Army Cavalry Sergeant 1866 by Oliver H. Willard
You've probably heard of the blue and the grey when people refer to the civil war sides. The Northern Union armies wore navy blue and the Southern Confederate armies wore grey. However, the uniforms weren't exactly "uniform" at the start of the war.
At the Start of the War
When the Civil War first began, neither side thought it would turn into a major conflict. They weren't ready for a major war against each other. One of the things they weren't ready for was having uniforms for the armies.
At first, uniforms were provided to the soldiers by the states and local cities. The materials, colors, and styles were all different. The north tried to get their soldiers to all wear navy blue uniforms, but they often ran out of blue cloth and had to use grey. The materials and styles were different too, depending on where a soldier came from.
Confusion on the Battlefield
The lack of consistent uniforms led to confusion on the battlefield. In some early battles soldiers often shot people from their own side. Eventually, the uniforms became more standard with the Union army wearing navy colored uniforms and the Confederates wearing grey.
The Union uniform consisted of a dark blue wool coat with light blue trousers and a dark cap called a forage cap. They typically wore shoes that went up to their ankles called "brogans".
The coat often had bright buttons that sometimes indicated the rank of the soldier or what state they represented. Other markings on the coat like piping or badges usually indicated the rank of the soldier.
Campaign hat worn by General Sherman Photo by Ducksters
Confederate Cavalrymen by George B. Davis, Leslie J. Perry, and Joseph W. Kirkleys
The Confederate Uniforms were less standard than the Union's. At the start of the war, many Confederate soldiers just wore their own clothes into battle. Eventually they settled on a uniform that had a waist length grey coat and light blue trousers.
Due to costs and a lack of materials during the war, many Confederate soldiers did not have adequate uniforms. They often wore combinations of what they could find and steal as well as their own clothes. They also didn't have very good shoes and sometimes had to go without any shoes at all.
The typical soldier had a musket or rifle and possibly a knife or a sword for close combat. Some rifles had bayonets at the end that they would use for close combat. Officers often had pistols and a sword to fight with.
Soldiers carried their other gear in a backpack called a knapsack. They carried a blanket, a fry pan for cooking, and a canteen for water. Other items often included a comb, a sewing kit to repair their uniforms, silverware, a Bible, and a pocket knife.
Green hat worn by Union sharpshooters Photo by Ducksters
Interesting Facts about Civil War Uniforms
The uniforms were mostly made from wool, which was very hot during the summers. Many soldiers suffered from heat exhaustion on long marches as a result.
The Union Army settled on rules for an official uniform in 1862. It wasn't until 1863 that the Confederate Army began to use a standard uniform design.
The Confederates chose gray dye for their uniforms because it was inexpensive to make.
Sometimes the grey coats of the Confederates were trimmed with green or yellow.