Black Elk, also known as Heȟáka Sápa and baptized as Nicholas Black Elk, was a prominent wičháša wakȟáŋ ("medicine man, holy man") and heyoka of the Oglala Lakota people. He was born on December 1, 1863, and passed away on August 19, 1950.

Black Elk was a second cousin of the war leader Crazy Horse and participated in significant historical events such as the Battle of Little Bighorn and the Wounded Knee Massacre. His experiences and visions were documented by poet John Neihardt in the book Black Elk Speaks, published in 1932, which remains an important work for understanding Native American spirituality.

Later in life, Black Elk converted to Catholicism and became a catechist while continuing to practice Lakota ceremonies. His stories and religious views gained attention through his collaboration with American ethnologist Joseph Epes Brown for the book The Sacred Pipe in 1947.

Black Elk's dedication to his spiritual mission and his dual practice of Catholicism and Lakota traditions demonstrate his unique role as a spiritual leader. In 2016, the Roman Catholic Diocese of Rapid City opened a cause for his beatification within the Church.