© Public Domain/Getty Images

Many foreigners enlisted in the American Civil War -

It’s estimated that about 13% of America’s population was born outside the country when the war broke out in 1861.

© Getty Images

Most foreigners fought for the Union Army -

Foreign-born soldiers served both in the Union Army and alongside Confederate soldiers. However, their presence was much stronger in the Union, where they are estimated to have represented about a quarter of the entire army.

© Getty Images

Germans -

Some 216,000 German-born soldiers joined the Union Army. They were joined by about 250,000 German-Americans. Germans made up the largest foreign ethnic group fighting for the North. Pictured is the German Division of the Army of the Potomac.

© Public Domain

Irish -

The Irish fought on both sides of the conflict, but most for the North. It’s estimated that about 160,000 Irish soldiers joined the Union Army, whereas 20,000 Irish fought alongside Confederacy soldiers.

© Getty Images

Irish -

In addition to those born in Ireland, a number of Irish Americans also fought in the conflict. The Union Army's Irish Brigade was made up of Irish Americans.

© Getty Images

Irish -

Several Irish Infantry Regiments were present in major battles and campaigns, including the 69th New York Infantry Regiment (pictured), the 63rd Infantry Regiment, the 88th New York Infantry, and the 28th Massachusetts Infantry Regiment.

© Public Domain

Other Europeans -

Other Europeans joined the conflict, including Italian, French, Hungarian, Polish, Swiss, and Spaniards, among others.

© Public Domain

Multiethnic regiment -

The 39th New York Infantry Regiment, aka the "Garibaldi Guard" is an example of how multiethnic the Civil War was.

© Public Domain

Multiethnic regiment -

The regiment was led by Hungarian colonel Frederick George D'Utassy (pictured, right) and had soldiers of many nationalities.

© Getty Images

Multiethnic regiment -

Initially, the regiment was divided into eleven companies of men from different national backgrounds, including Italian, German, Hungarian, Swiss, French, Spanish, and Portuguese. Pictured is Captain Carlos Alvarez de la Mesa, a Spaniard who served in the multiethnic regiment.

© Public Domain

Foreign-born Confederate soldiers -

Of course, there were also foreign-born troops fighting for the Confederate Army, including Irish, German, Polish, French, Spanish, Mexican, and Cuban soldiers, among others.

© Getty Images

Notable foreign Confederate soldier -

One notable example is French Major General Count Camille Armand Jules Marie, Prince de Polignac, who led the Confederate victory at the Battle of Mansfield.

© Public Domain

Chinese soldiers -

While most foreign soldiers were Europeans, there were also men from other nationalities in both sides of the conflict, namely Chinese soldiers. It’s estimated that about 50 Chinese men fought in the Civil War, most of them for the Union. Pictured is Union soldier Joseph Pierce.

© Public Domain

Asian-Americans -

In addition, Asian-Americans with Chinese, Japanese, Indian, and Filipino heritage, as well as others, fought in the Civil War. Pictured is Corporal Felix Cornelius Balderry, a Filipino soldier who fought for the Union.

© Public Domain

Native Americans -

Many Native Americans also fought in the conflict. These included the Catawba, the Cherokee, the Choctaw, and the Seminole. Most  (though not all) sided with the Confederacy. Pictured is Confederate Brigadier General Stand Watie, the only Native American to become a general in the Civil War.

© Public Domain

African Americans -

It’s estimated that some 186,097 African Americans fought in the Civil War. Many sided with the Union, joining Union Army regiments called United States Colored Troops (USCT).

© Public Domain

African Americans -

Many African Americans also served the Confederacy, although largely as slaves or semi-free laborers who did not qualify as soldiers. Pictured is Marlboro Jones, who worked as a servant to a white Confederate soldier.

© Public Domain

Children -

Underage soldiers were abundant during the conflict. In fact, it’s estimated that about a fifth of all military personnel were under eighteen. In the Union Army alone, about 100,000 soldiers were fifteen or less.

© Public Domain

Children -

Young soldiers would mostly occupy non-combat positions. They’d be drummer boys, buglers, cooks and nurse assistants, or “powder monkeys” in Navy warships.

© Public Domain

Children -

Playing the drums was one of the most popular positions for kids during the conflict.

© Public Domain

Children -

Things were a bit different for children at sea, where they’d commonly work as “powder monkeys,” rushing gunpowder into canons.

© Getty Images

A kid who made history in the Union army -

John Klem was nine years old when he ran away from home to enlist in the Union Army. He changed his name to John Lincoln Clem and after being rejected by many regiments due to his age and size, he managed to join the 22nd Michigan Infantry regiment.

© Getty Images

A kid who made history in the Union army -

Clem was a drummer boy for some time and officially enlisted at age 12. He then made history by killing a Confederate colonel at the Battle of Chickamauga. Clem was promoted to sergeant, the youngest ever, in the US Army.

© Public Domain

A kid who made history in the Union army -

John Klem went on to graduate from high school and rejoin the Army in 1871. He retired as a brigadier general. In 1916, after retirement, Clem was promoted to the rank of major general.

© Public Domain

The bugler boy of the “Mozart Regiment” -

A young Gustav Albert Schurmann fled Prussia with his father and ended up joining the 40th New York Volunteer Infantry, which became known as the “Mozart Regiment” because it had so many musicians.

© Public Domain

The bugler boy of the “Mozart Regiment” -

Gustav became the principal bugler and was a constant presence on the front lines. He ended up saving General Sickles’ life (pictured), which won him medals and a commendation from President Lincoln. Interestingly, later Gustav became friends with Tad, Lincoln’s youngest son.

© Public Domain

Senior soldiers -

On the other side of the spectrum, there were also senior citizens joining the war. Fifty-year-old George W. Kincaid led the 37th Iowa Infantry Regiment, which was composed of men over 45.

© Getty Images

Senior soldiers -

The idea was a success and over 1,000 men signed up to join the 37th Iowa Infantry Regiment, which was then nicknamed the "Graybeard Regiment."

© Getty Images

Senior soldiers -

The average age of the "Graybeard Regiment” was 57, and there were men aged from forties to seventies fighting for the Union. Pictured is Henry Otis Pratt, who served in the 37th Iowa Infantry Regiment.

© Public Domain

Senior soldiers -

“The Graybeards”’ mostly performed non-combat duties, including guarding prison camps and protecting supply trains, etc. More died of disease than in battle, where only three men perished.

Sources: (Time) (History Collection) (American Battlefield Trust) (History Net) (Military History Now) (Military Network) (National Museum of the United States Navy)

© Getty Images