Question: The Battle of Cedar Mountain, also known as Slaughter's Mountain or Cedar Run, took place on August 9, 1862, in Culpeper County, Virginia, as part of the American Civil War, Union forces under which Maj. Gen., that was an American politician from Massachusetts and a Union general during the Civil War, attacked Confederate forces under Maj. Gen. Thomas J. "Stonewall" Jackson near Cedar Mountain?

full_context: Document 1: Second Battle of Bull Run: The Second Battle of Bull Run or Battle of Second Manassas was fought August 28–30, 1862 in Prince William County, Virginia, as part of the American Civil War. It was the culmination of the Northern Virginia Campaign waged by Confederate Gen. Robert E. Lee's Army of Northern Virginia against Union Maj. Gen. John Pope's Army of Virginia, and a battle of much larger scale and numbers than the First Battle of Bull Run (or "First Manassas") fought on July 21, 1861 on the same ground.
Document 2: Manassas National Battlefield Park: Manassas National Battlefield Park, located north of Manassas, in Prince William County, Virginia, preserves the site of two major American Civil War battles: the First Battle of Bull Run on July 21, 1861, and the Second Battle of Bull Run which was fought between August 28 and August 30, 1862 (also known as the "First Battle of Manassas" and the "Second Battle of Manassas", respectively). The peaceful Virginia countryside bore witness to clashes between the armies of the North (Union) and the South (Confederacy), and it was there that Confederate General Thomas J. Jackson acquired his nickname "Stonewall."
Document 3: Battle of Cedar Mountain: The Battle of Cedar Mountain, also known as Slaughter's Mountain or Cedar Run, took place on August 9, 1862, in Culpeper County, Virginia, as part of the American Civil War. Union forces under Maj. Gen. Nathaniel P. Banks attacked Confederate forces under Maj. Gen. Thomas J. "Stonewall" Jackson near Cedar Mountain as the Confederates marched on Culpeper Court House to forestall a Union advance into central Virginia. After nearly being driven from the field in the early part of the battle, a Confederate counterattack broke the Union lines resulting in a Confederate victory. The battle was the first combat of the Northern Virginia Campaign.
Document 4: Battle of Chantilly: The Battle of Chantilly (or Ox Hill, the Confederate name) took place on September 1, 1862, in Fairfax County, Virginia, as the concluding battle of the Northern Virginia Campaign of the American Civil War. Thomas J. "Stonewall" Jackson's corps of the Army of Northern Virginia attempted to cut off the line of retreat of the Union Army of Virginia following the Second Battle of Bull Run but was attacked by two Union divisions. During the ensuing battle, Union division commanders Isaac Stevens and Philip Kearny were both killed but the Union attack halted Jackson's advance.
Document 5: Orville E. Babcock: Orville Elias Babcock (December 25, 1835 – June 2, 1884) was an American Civil War General in the Union Army. He graduated third in his class at the United States Military Academy at West Point in 1861, and served in the United States Army Corps of Engineers throughout the Civil War. As Assistant Engineer and aide-de-camp for district commander Nathaniel P. Banks, in 1862 Babock worked on fortifications to aid in defending the nation's capitol from Confederate attack. Babcock later served as aide-de-camp for Ulysses S. Grant and participated in the Overland Campaign. He was promoted to Brevet Brigadier General in 1865 and continued on Grant's staff during Reconstruction. After Grant became President in 1869, Babcock was appointed Superintendent of Public Buildings and Grounds for Washington, DC and Secretary to the President of the United States—in modern terms, the chief of staff—and he served in both posts until 1876. Upon his appointment Babcock was young and ambitious, and considered the Iago of the Grant administration. In 1869, Grant sent Babcock on a mission to explore the possibility of annexing the island nation of Santo Domingo to the United States.
Document 6: Ulysses S. Grant: Ulysses S. Grant, born Hiram Ulysses Grant , (April 27, 1822 – July 23, 1885) was the Commanding General of the United States Army at the end of the American Civil War and later the 18th President of the United States from 1869 to 1877. As Commanding General, Grant worked closely with President Abraham Lincoln to lead the Union Army to victory over the Confederacy in the Civil War. Supported by Congress, Grant implemented Reconstruction, often at odds with President Andrew Johnson. Twice elected president, Grant led the Republicans in their effort to remove the vestiges of Confederate nationalism and slavery, protect African-American citizenship, and support economic prosperity. Although his presidency has often been criticized for multiple administration scandals and for his failure to alleviate the economic depression following the Panic of 1873, he is regarded as a President who performed relatively well in the context of his time and pursued justice for all.
Document 7: Cedar Mountain, Virginia: Cedar Mountain, also known as Slaughter Mountain, is a piedmont monadnock in Culpeper County, Virginia. The 800 ft ridge is 7 mi south of the town of Culpeper and just to the northwest of the northern tip of the Southwest Mountains at Clark Mountain. The mountain was the site of the Battle of Cedar Mountain in 1862 during the Northern Virginia Campaign of the American Civil War.
Document 8: Northern Virginia Campaign: The Northern Virginia Campaign, also known as the Second Bull Run Campaign or Second Manassas Campaign, was a series of battles fought in Virginia during August and September 1862 in the Eastern Theater of the American Civil War. Confederate General Robert E. Lee followed up his successes of the Seven Days Battles in the Peninsula Campaign by moving north toward Washington, D.C., and defeating Maj. Gen. John Pope and his Army of Virginia.
Document 9: Lewis Henry Douglass: Lewis Henry Douglass (1840–1908) was the oldest son of Frederick Douglass and his first wife Anna Murray Douglass. He was born in New Bedford, Massachusetts. Douglass was well educated and as a boy apprenticed, in Rochester, New York, as a typesetter for his father's newspapers "The North Star" and "Douglass' Weekly". He joined the Union Army on March 25, 1863, only two months after the Emancipation Proclamation allowed African Americans to see combat in the Union Army. He fought for one of the first official African American units in the United States during the Civil War, the famed 54th Massachusetts Infantry Regiment. Shortly after joining the army, Douglass attained the rank of Sergeant Major, the highest rank a black man could reach. He took part in the Battle of James Island, the Battle of Olustee, the Second Battle of Fort Wagner. At the Second Battle of Fort Wagner, half of his regiment was killed, but this battle turned the public's attention toward the sacrifices made by African Americans in the war. Douglass addressed the bravery of the African American troops in a letter to his future wife Helen Amelia Loguen:
Document 10: Battle of Beaver Dam Creek: The Battle of Beaver Dam Creek, also known as the Battle of Mechanicsville or Ellerson's Mill, took place on June 26, 1862, in Hanover County, Virginia, as the first major engagement of the Seven Days Battles during the Peninsula Campaign of the American Civil War. It was the start of Confederate General Robert E. Lee's counter-offensive against the Union Army of the Potomac, under Maj. Gen. George B. McClellan, which threatened the Confederate capital of Richmond. Lee attempted to turn the Union right flank, north of the Chickahominy River, with troops under Maj. Gen. Thomas J. "Stonewall" Jackson, but Jackson failed to arrive on time. Instead, Maj. Gen. A.P. Hill threw his division, reinforced by one of Maj. Gen. D.H. Hill's brigades, into a series of futile assaults against Brig. Gen. Fitz John Porter's V Corps, which occupied defensive works behind Beaver Dam Creek. Confederate attacks were driven back with heavy casualties. Porter withdrew his corps safely to Gaines Mill.
Document 11: Henry Goddard Thomas: Brigadier General and Brevet Major General Henry Goddard Thomas (April 5, 1837 – January 23, 1897) was a Union general in the American Civil War. A native of Portland, Maine, Thomas graduated from Amherst College in 1858 and was admitted to the bar shortly thereafter. He enlisted as a private in the 5th Maine Volunteer Infantry Regiment. Promoted to captain in June 1861, Thomas was present at the First Battle of Bull Run and the Peninsula Campaign among other battles. In February 1863, Thomas was appointed colonel of the 2nd United States Colored Infantry. In December 1863, Thomas was appointed colonel of the 19th United States Colored Infantry. On November 30, 1864, President Abraham Lincoln appointed Thomas a brigadier general of volunteers to rank from his appointment date. The President nominated Thomas for the appointment on December 12, 1864 and the U.S. Senate confirmed the promotion on February 23, 1865. Thomas was mustered out of the volunteers on January 15, 1866. On March 29, 1867, President Andrew Johnson nominated Thomas for appointment to the grade of brevet major general of volunteers for his service during the war, to rank from March 13, 1865, and the U.S. Senate confirmed the award on April 5, 1867. Henry Goddard Thomas died in January 23, 1897 in Oklahoma City Indian Territory (Oklahoma) and is interred at Evergreen Cemetery in Portland, Maine.
Document 12: Abraham Lincoln: Abraham Lincoln ( ; February 12, 1809 – April 15, 1865) was an American politician and lawyer who served as the 16th President of the United States from March 1861 until his assassination in April 1865. Lincoln led the United States through its Civil War—its bloodiest war and perhaps its greatest moral, constitutional, and political crisis. In doing so, he preserved the Union, paved the way to the abolition of slavery, strengthened the federal government, and modernized the economy.
Document 13: Elihu B. Washburne: Elihu Benjamin Washburne (September 23, 1816 – October 23, 1887) was an American politician and diplomat. A member of the Washburn family, which played a prominent role in the early formation of the United States Republican Party, he served as a congressman from Illinois before and during the American Civil War. He was a political ally of President Abraham Lincoln and General (later President) Ulysses S. Grant. During Grant's administration, Washburne was the 25th United States Secretary of State, briefly in 1869, and was the United States Minister to France from 1869 to 1877.
Document 14: Camp Stanton: Camp Edwin M. Stanton (usually known as just Camp Stanton) was an American Civil War training camp that existed from 1861-1862 in Lynnfield, Massachusetts. When the camp first opened in 1861, it was known as Camp Schouler, named for Massachusetts Adjutant General William Schouler. After President Abraham Lincoln's call for 300,000 troops in July 1862, the camp was revived and renamed in honor of United States Secretary of War Edwin M. Stanton. It served as the training camp and rendezvous for recruits from Eastern Massachusetts (recruits from Western Massachusetts were sent to Camp Wool in Worcester, Massachusetts). Soldiers stationed at Camp Schouler/Stanton during training included Edward A. Wild, Henry Wilson, Nelson A. Miles, Edward Winslow Hinks, and Arthur F. Devereux. During World War I it was renamed Camp Houston and served as a Massachusetts National Guard mobilization camp in 1917. It was located on the Newburyport Turnpike (now part of U.S. Route 1) near the Peabody, Massachusetts line. The camp was divided into streets, with tents and cook houses located on both sides of the Turnpike to Suntaug Lake.
Document 15: Nathaniel P. Banks: Nathaniel Prentice (or Prentiss) Banks (January 30, 1816 – September 1, 1894) was an American politician from Massachusetts and a Union general during the Civil War.
ground_truth: Nathaniel Prentice (or Prentiss) Banks