Yes Mahmoud There was a Holocaust
"Within weeks of Hitler’s 1933 rise to power, the iron gates slammed shut on inmates of the first Nazi concentration camps. It was the start of an unparalleled experiment in persecution and genocide that expanded over the next 12 years into a pyramid of ghettos, Gestapo prisons, slave labor camps and, ultimately, extermination factories. . . . Couched in patronizing and dehumanizing language, documents from the earliest camps foreshadow a system that would define the word 'genocide.' They show that years before the mass-scale killings began at death camps such as Auschwitz, the intellectual groundwork of viewing categories of humanity as subhuman was already in place. . . .When they began work six years ago, [project director] Megargee said the researchers estimated 5,000 to 7,000 sites existed. 'Based on our research, it is now clear that there were over 20,000 such sites in Germany, in German-occupied territories and in the states allied with Nazi Germany." - from an AP 2005 report
The picture above is from a series painted from memory by Johannes Steyer, a Jehovah's Witness incarcerated at Buchenwald as #1795. The text is translated as "Jehovah's Witnesses (Bible Students) before them, a group of Jews struggling to carry stones from a quarry."