Question: Why did Elizabeth Bacon Custer's husband die?

Knowledge 1: Elizabeth Bacon Custer
Elizabeth Clift Custer (née Bacon; April 8, 1842 – April 4, 1933) was an American author and public speaker, and the wife of Brevet Major General George Armstrong Custer, United States Army.She spent most of their marriage in relatively close proximity to him despite his numerous military campaigns in the American Civil War and subsequent postings on the Great Plains as a commanding officer in the United States Cavalry.Left nearly destitute in the aftermath of her husband's death, she became an outspoken advocate for his legacy through her popular books and lectures.Largely as a result of her decades of campaigning on his behalf, General Custer's iconic image as the gallant fallen hero amid the glory of Custer's Last Stand was a canon of American history for almost a century after his death.Elizabeth Custer never remarried and reached age 90 when she died in 1933, only four days short of her 91st birthday.She has been portrayed by a number of actresses, starting in the 1940s in films and on television. [SEP] Knowledge 2: George Armstrong Custer
Custer graduated from West Point in 1861 at the bottom of his class, but as the Civil War was just starting, trained officers were in immediate demand.He worked closely with General McClellan and the future General Pleasonton, both of whom recognized his qualities as a cavalry leader, and he was brevetted brigadier general of volunteers at age 23.Only a few days after his promotion, he fought at Gettysburg, where he commanded the Michigan Cavalry Brigade and despite being outnumbered, defeated J. E. B. Stuart's attack at what is now known as the East Cavalry Field.In 1864, Custer served in the Overland Campaign and in Sheridan's army in the Shenandoah Valley, defeating Jubal Early at Cedar Creek.His division blocked the Army of Northern Virginia's final retreat and received the first flag of truce from the Confederates, and Custer was present at Robert E. Lee's surrender to Ulysses S. Grant at Appomattox.After the war, Custer was appointed a lieutenant colonel in the Regular Army and was sent west to fight in the Indian Wars.On June 25, 1876, while leading the 7th Cavalry Regiment at the Battle of the Little Bighorn in Montana Territory against a coalition of Native American tribes, he was killed along with over one third of his command during an action later romanticized as "Custer's Last Stand".His dramatic end was as controversial as the rest of his career, and reaction to his life and career remains deeply divided.Custer's bold leadership in battle is unquestioned, but his legend was partly of his own fabrication through his extensive journalism, and perhaps more through the energetic lobbying of his wife Libbie Custer throughout her long widowhood.
Knowledge 1: George Armstrong Custer
Custer graduated from West Point in 1861 at the bottom of his class, but as the Civil War was just starting, trained officers were in immediate demand.He worked closely with General McClellan and the future General Pleasonton, both of whom recognized his qualities as a cavalry leader, and he was brevetted brigadier general of volunteers at age 23.Only a few days after his promotion, he fought at Gettysburg, where he commanded the Michigan Cavalry Brigade and despite being outnumbered, defeated J. E. B. Stuart's attack at what is now known as the East Cavalry Field.In 1864, Custer served in the Overland Campaign and in Sheridan's army in the Shenandoah Valley, defeating Jubal Early at Cedar Creek.His division blocked the Army of Northern Virginia's final retreat and received the first flag of truce from the Confederates, and Custer was present at Robert E. Lee's surrender to Ulysses S. Grant at Appomattox.After the war, Custer was appointed a lieutenant colonel in the Regular Army and was sent west to fight in the Indian Wars.On June 25, 1876, while leading the 7th Cavalry Regiment at the Battle of the Little Bighorn in Montana Territory against a coalition of Native American tribes, he was killed along with over one third of his command during an action later romanticized as "Custer's Last Stand".His dramatic end was as controversial as the rest of his career, and reaction to his life and career remains deeply divided.Custer's bold leadership in battle is unquestioned, but his legend was partly of his own fabrication through his extensive journalism, and perhaps more through the energetic lobbying of his wife Libbie Custer throughout her long widowhood. [SEP] Knowledge 2: Margherita Gonzaga, Duchess of Lorraine
Margherita Gonzaga (2 October 1591 – 7 February 1632) was Duchess of Lorraine from 1606 until her husband's death in 1624.
Knowledge 1: Elizabeth Bacon Custer
Elizabeth Clift Custer (née Bacon; April 8, 1842 – April 4, 1933) was an American author and public speaker, and the wife of Brevet Major General George Armstrong Custer, United States Army.She spent most of their marriage in relatively close proximity to him despite his numerous military campaigns in the American Civil War and subsequent postings on the Great Plains as a commanding officer in the United States Cavalry.Left nearly destitute in the aftermath of her husband's death, she became an outspoken advocate for his legacy through her popular books and lectures.Largely as a result of her decades of campaigning on his behalf, General Custer's iconic image as the gallant fallen hero amid the glory of Custer's Last Stand was a canon of American history for almost a century after his death.Elizabeth Custer never remarried and reached age 90 when she died in 1933, only four days short of her 91st birthday.She has been portrayed by a number of actresses, starting in the 1940s in films and on television. [SEP] Knowledge 2: Margherita Gonzaga, Duchess of Lorraine
Margherita Gonzaga (2 October 1591 – 7 February 1632) was Duchess of Lorraine from 1606 until her husband's death in 1624.

Answer: Battle of the Little Bighorn