This long tradition continued into the nineteenth century. By the 1800s most Irishmen who wanted to serve as soldiers joined the British army. However, the more adventurous or independent minded went further afield. In the 1850s the Papal States, a sovereign country in the middle of the Italian peninsula felt threatened by the expanding drive for Italian unity. The Pope launched an appeal for Catholic volunteers for the Papal Army and hundreds of enthusiastic Irishmen travelled to Rome and joined up. One of these volunteers was Myles Keogh, from Leighlinbridge in County Carlow. Keogh was from a farming family and when he joined the Papal Army his soldierly qualities were quickly recognised and he was commissioned as a lieutenant. Lieutenant Keogh saw action when the Papal States were invaded by Italian Unification forces in 1860, particularly at the siege of Ancona, the last action of the war which took place in September 1860. Myles remained in the Papal Army when the majority of the Irish volunteers returned home and when he finally left Papal service in 1862 he did so as a highly decorated officer.
Like many of the Irish volunteers in the Papal army Myles Keogh emigrated to the USA where he joined the US army. Keogh was also commissioned as an officer in the US army. He fought in many battles during the American Civil War, most notably at Antietam and Gettysburg. Keogh was even captured by the Confederates in 1864 but was soon released. He ended the Civil War with the rank of lieutenant colonel.
After the Civil War Keogh continued his military career as a soldier in the US cavalry. With the rank of captain he served in the famous 7th Cavalry regiment under General Custer for many years. In 1869 Myles returned to Ireland on leave to visit his brothers and sisters and help them out financially.
Captain Myles Keogh commanded a company of the 7th Cavalry at the battle of the Little Big Horn fought against the Sioux and Cheyenne Native American tribes in June 1876. Captain Keogh was one of those killed in the massacre of Custer's command. While it is not certain what happened it appears that Myles Keogh fought bravely to the end as his body was later found by his friend and fellow Irishman Lieutenant James Nowlan surrounded by the bodies of his loyal NCOs and standard bearers. Lieutenant Nowlan also found Myles's horse Comanche, the only living creature on the battlefield, standing close to his master's body. Comanche was kept as much loved pet by the 7th Cavalry until she died in 1891.
Captain Myles Keogh is one of the most famous Irishmen who served in the US army in the Nineteenth century. However, there were hundreds of others. Irish soldiers were highly regarded in the US army being noted for their loyalty and good conduct. In return the US army gave many Irishmen a great start to their new life in the United States, providing employment and fresh opportunity to the new emigrants. Irishmen like Myles Keogh continued the proud traditions of their ancestors of previous centuries and proved themselves to be as determined and adventurous as their fellow countrymen who once served in the Spanish, French and other European armies.