Thomas Francis Meagher, the controversial and flamboyant commander of the famed Irish Brigade (2nd Brigade, 1st Division, Second Army Corps, Army of the Potomac) at the Battle of Antietam (Sharpsburg), was an immigrant from Ireland by way of Tasmania near Australia. As a young lawyer in his native Waterford, Ireland, Meagher became heavily involved in the Young Ireland movement which believed that non-violent means was not going to secure independence and freedom for Ireland from Great Britain. For his part in an abortive uprising in 1848, Meagher and six others were tried, convicted and banished to the penal colony on the island of Tasmania. They managed to escape and made their way to America, landing in New York. In that city Meagher quickly became not only a leading member of the local Democratic Party but built a fairly successful law practice. It also helped him considerably to marry the daughter of one of the leading members of New York society at the time.
As tensions rose with the threats of the secession of the several Southern states from the Union, Meagher (as did many Irishmen) initially supported the viewpoint of the South. However, when it became later known the South was actively courting the support of Great Britain, their mortal enemy, many Irish joined and fought with the Union armies.
With the coming of war after the attack on Fort Sumter, Meagher volunteered his services and quickly rose what would, about eighteen months later, be known as the famed Irish Brigade. The Sixty-ninth New York and the Sixty-third New York regiments fought under Meagher at the Battle of First Bull Run. With the addition of the Eighty-eighth New York, the nucleus of the brigade also known as "Meagher's Boys" took shape.
The Irish Brigade won glory not only during the bloody assault on the Sunken Road at Antietam but even more so in their doomed but valiant charge against the fortified Confederate position at the Sunken Road at the foot of Marye's Heights at the Battle of Fredericksburg. Because the Irish Brigade had yet to receive their new battle flags, the members of the brigade put sprigs of boxwood in their caps as they advanced against the entrenched Confederates at Fredericksburg. The famed Civil War artist Don Troiani in one of his paintings, known as "Clear the Way!", has commemorated this advance and act.
Meagher was also a controversial figure inside the Army of the Potomac. Some accused him of being drunk on the day he led his brigade against the North Carolinians of George B. Anderson's brigade of D. H. Hill's Confederate division. As Meagher and his men passed over the crest on a part of the Roulette farm that hid them from the waiting Confederate Iine in the Sunken Road, the defenders loosed a volley that not only tumbled Meagher's horse down upon him. Suffering concussive injuries, Meagher was badly stunned and certainly looked, upon a quick glance, to be drunk.
After the Irish Brigade received decimating losses in the attack on the Sunken Road at Antietam and then again at the Sunken Road at the base of Marye's Height at Fredericksburg, the unit was but a shadow of its former proud self. Attempting to receive permission to return to New York to recruit new members for the brigade, Meagher resigned his commission after being rebuffed in his efforts. He later served in a minor capacity toward the end of the War, but never again as an active leader of men on the line.
After the Civil War, Meagher returned to New York and attempted to return to civilian life. He also unsuccessfully tried to enlist support for the Irish Republican Brotherhood to attempt to seize British Canada as a bargaining chip for Irish independence. As he had during his military service, he had his friends and his enemies. Meagher eventually moved west to the Montana Territory where he served briefly as Territorial Secretary. When the Territorial Governor resigned, Meagher became, in effect Territorial Governor. While on a steamboat one night on the Missouri River, he fell overboard and drowned. His death was ruled accidental, probably due to being drunk, although some have speculated he might have been murdered. His body was never recovered.
Thomas Francis Meagher, a Son of Erin and Irish Patriot, was also one of the more colorful commanders of either side during the American Civil War.