Final answer:
The flagellants were Christian believers who practiced self-flagellation during the Black Death, believing this could atone for sins and end the plague but were condemned by the Pope and disappeared by the fifteenth century.
Step-by-step explanation:
The flagellants were Christian believers who emerged during the time of the Black Death in medieval Europe. They practiced self-flagellation, believing that this penance could atone for humanity's sins and perhaps halt the plague. By publicly flogging themselves until they bled, they hoped to earn divine mercy.
This extreme expression of faith began in Eastern Europe and spread to Germany, then further through Europe. With a message that sometimes became anti-Semitic, they accused Jewish citizens of causing the plague. The increasing radicalism of this group led to their condemnation by Pope Clement VI in 1349, and their movement eventually disappeared by the fifteenth century.