Question: Which abolitionist movement involved a term that came to prominence just before the American Civil War in Bleeding Kansas?

Context paragraphs:
John Brown (abolitionist): John Brown (May 9, 1800 – December 2, 1859) was an American abolitionist who believed and advocated that armed insurrection was the only way to overthrow the institution of slavery in the United States.  Brown first gained attention when he led small groups of volunteers during the Bleeding Kansas crisis of 1856.  Dissatisfied with the pacifism of the organized abolitionist movement, he said, "These men are all talk.  What we need is action—action!"  During the Kansas campaign, Brown commanded forces at the Battle of Black Jack and the Battle of Osawatomie.  He and his supporters killed five supporters of slavery in the Pottawatomie massacre of May 1856 in response to the sacking of Lawrence by pro-slavery forces.

James Montgomery (colonel): James Montgomery (December 22, 1814 – December 6, 1871) was a Jayhawker during the Bleeding Kansas Affair and a controversial Union colonel during the American Civil War.  Montgomery was a staunch abolitionist and used extreme measures against pro-slavery populations.

Jayhawker: Jayhawkers is a term that came to prominence just before the American Civil War in Bleeding Kansas, where it was adopted by militant bands affiliated with the free-state cause.  These bands, known as "Jayhawkers", were guerrilla fighters who often clashed with pro-slavery groups from Missouri known at the time as "Border Ruffians".  After the Civil War, the word "Jayhawker" became synonymous with the people of Kansas.  Today a modified version of the term, Jayhawk, is used as a nickname for a native-born Kansan, but more typically for a student, fan, or alumnus of the University of Kansas.

Lane County, Kansas: Lane County (standard abbreviation: LE) is a county located in the U.S. state of Kansas.  As of the 2010 census, the county population was 2,150, making it the third-least populous county in Kansas.  The county seat is Dighton, the only city in the county.  The county was named after James H. Lane who was a leader of the Jayhawker abolitionist movement and served as one of the first U.S. Senators from Kansas.

David Goodman Croly: David Goodman Croly (November 3, 1829 – April 29, 1889) was an American journalist, born in Ireland and educated at New York University.  He was associated with the "Evening Post" and the "Herald" (1854–58), and then became an editor and subsequently the managing editor of the "World".  He married Jane Cunningham, known as "Jennie June", in 1856.  In 1863, during the Civil War, he co-authored the anonymous pamphlet "Miscegenation", which tried to discredit the abolitionist movement and the Lincoln Administration by playing on racist fears common among whites.  The anonymous author of the pamphlet claimed to be an Abolitionist in favour of promoting the intermarriage of whites and blacks, a taboo practice that at the time was seen as a threat to white supremacy.  The pamphlet coined the term miscegenation for the intermixing of races.

Battle of Black Jack: The Battle of Black Jack took place on June 2, 1856, when anti-slavery forces, led by the noted abolitionist John Brown, attacked the encampment of Henry C. Pate near Baldwin City, Kansas.  The battle is cited as one incident of "Bleeding Kansas" and a contributing factor leading up to the American Civil War of 1861 to 1865.

George T. Downing: George T. Downing (December 30, 1819 – July 21, 1903) was an abolitionist and activist for African-American civil rights.  His father was a caterer and Oyster seller in Philadelphia and New York City and George followed the same career path in New York, Newport, Rhode Island, and Washington, DC.  From the 1830s until the end of slavery, Downing was active in the abolitionist movement and in the Underground Railroad, with his restaurant serving as a rest house.  During the American Civil War (1861-1865), Downing helped recruit African American soldiers.  After the war he moved to Washington, DC where he ran the Refectory for the House of Representatives.  He was a prominent member in the Colored Conventions Movement and worked to join the efforts of women's rights and black rights.  He became close to Charles Sumner and was with the legislator when he died.  Late in his life he returned to Rhode Island where he continued to be a community leader and civil rights activist.

Philip H. Murray: Philip H. Murray (1842 - February 17, 1917) was an abolitionist, journalist, phrenologist, and civil rights activist who spent most of his career in St. Louis, Missouri.  He grew up in Reading, Pennsylvania where he participated in the abolitionist movement in that region.  During the US Civil War he continued his work and served as a recruiting officer to help enlist blacks into the Union Army.  After the war, he focused on journalism.  In 1867, he established the first black newspaper in Kentucky, "The Colored Kentuckian".  He later moved to St. Louis where he continued to work in journalism and as an advocate for black education and civil rights.  He was also the president of the first Negro Press Association.

August Bondi: August Bondi (Jewish name Anshl)(July 21, 1833, Vienna, Austria – 1907, United States) was involved in what he called the Border War, but is now usually called Bleeding Kansas, and latter the American Civil War.  In Kansas he fought with abolitionist John Brown.

Pottawatomie massacre: The Pottawatomie massacre occurred during the night of May 24 and the morning of May 25, 1856.  In reaction to the sacking of Lawrence, Kansas by pro-slavery forces, John Brown and a band of abolitionist settlers—some of them members of the Pottawatomie Rifles—killed five settlers north of Pottawatomie Creek in Franklin County, Kansas.  This was one of the many bloody episodes in Kansas preceding the American Civil War, which came to be known collectively as Bleeding Kansas.  Bleeding Kansas was largely brought about by the Missouri Compromise and the Kansas–Nebraska Act.

Supporting paragraphs: Lane County, Kansas Jayhawker
Answer: Jayhawker