It is an oft repeated lie. If it was well documented you would be able to present such documentation.
References noted.
We see it in the slaughter of the Albigensians which was really the first Roman Catholic crusade intended to slay other Christians. [K.Deschner, Opus Diaboli, Reinbek 1987, 29]The Albigensians...viewed themselves as good Christians, but would not accept Roman Catholic rule, and taxes, and dictates. Then on the command of pope Innocent III in 1209, Bezirs (today France) was destroyed, all the inhabitants were slaughtered. Victims including Catholics refusing to turn over their neighbours and friends were up to 70,000. [H.Wollschlger: Die bewaffneten Wallfahrten gen Jerusalem, Zrich 1973.179-181]
In Carcassonne 8/15/1209, thousands were slain and in subsequent 20 years of war until nearly all Cathars (probably half the population of the Languedoc, today southern France) were exterminated. After the war ended (1229) the Inquisition was founded 1232to search and destroy any who did not hold to the what the church dictated.
The Waldensians, and many others were exterminated, in the persecution of the Cathar of Southern Europe, northern Italy, it is estimated one million victims of the . [H.Wollschlger: Die bewaffneten Wallfahrten gen Jerusalem, Zrich 1973.183]
The Spanish Inquisition killed untold numbers and the Spanish Inquisitor Torquemada alone allegedly responsible for 10,220 burnings. Of course we cant leave out John Huss, a critic of papal infallibility and indulgences, who was burned at the stake in 1415.
In the 15th century we find the Church lauching a persecution against Hussites, with thousands slain. In 1538 pope Paul III declared a crusade against England who had left its domination and all English made as slaves of Church, but England being a island made that a bit difficult to implement. In the 1568, the Spanish Inquisition tribunal ordered extermination of 3 million rebels in (then Spanish) Netherlands and thousands were slain. In1572 In France about 20,000 Huguenots were killed on command of pope Pius V. Until 17th century 200,000 flee. [K.Deschner, Opus Diaboli, Reinbek 1987, 28-31]
In the Catholic 17th century 30 years' war against the Protestants, at least 40% of population decimated, mostly in Germany. [K.Deschner, Opus Diaboli, Reinbek 1987.31-32] And its recorded in the Catholics sack the city of Magdeburg/Germany, roughly 30,000Protestants were slain. "In a single church fifty women were found beheaded," reported poet Friedrich Schiller. [D.Stannard, American Holocaust, Oxford University Press 1992, 191. ]
Now this does not include the persecution and killing of the Jews which the church to say the least did not discourage and worse were instigated by its bishops or led by its priests. By the 4th and 5th centuries we see the beginning of this phase of the persecution as the Jewish synagogues were burned and many Jews slain. We find in the middle of the fourth century the first synagogue was destroyed on command of bishop Innocentius of Dertona in Northern Italy. The first synagogue known to have been burned down was near the river Euphrat, on command of the bishop of Kallinikon in the year 388. We find that as a result of the Council of Toledo 694, Jews were enslaved, their property confiscated, and their children forcibly baptized. The Bishop of Limoges (France) in 1010 had the cities' Jews, who would not convert to Christianity, expelled or killed. [K.Deschner, Abermals krhte der Hahn, Stuttgart 1962. 450-453]
When the Crusades began, thousands of Jews were slaughtered all through Europe as they marched to the Holy Land or just got together on their way there. History records the killing of the Jews at Worms, Mainz , Cologne, Neuss, Altenahr, Wevelinghoven, Xanten, Moers, Dortmund, Kerpen, Trier, Metz, Regensburg, Prag and others. [S.Eidelberg, The Jews and the Crusaders, Madison 1977.]
It continued in the Second Crusade in 1147. Several hundred Jews were slain in Ham, Sully, Carentan, and Rameru in France). [WW57] and it continued in the Third Crusade as English Jewish communities were attacked and sacked 1189/90. And in 1257-1267 the Jewish communities of London, Canterbury, Northampton, Lincoln, Cambridge, and others exterminated.
The killing of Jews with the churches knowledge if not outright approval continued through all Europe through the 13 century to what we see all the way to World War II by the Nazis. In Spain, Seville's the Jews were killed with the Archbishop Martinez leading. 4,000 were slain, 25,000 sold as slaves. Their identification was made easy by the brightly colored "badges of shame" that all jews above the age of ten had been forced to wear. [K.Deschner, Abermals krhte der Hahn, Stuttgart 1962. 454]
It was widespread in Poland with whole Jewish communities wiped out and the Jews killed. In the Chmielnitzki massacres of 1648 in Poland about 200,000 Jews were slain. And in Germany a Jew-killing craze reaches towns in Bavaria, Austria, Poland and in more than 350 towns in Germany all Jews murdered, mostly burned alive . And all Jews of Basel/Switzerland and Strasbourg/France were burned to death. [K.Deschner, Opus Diaboli, Reinbek 1987. 40-43]
ISIS/ISIL Muslim fanatics have nothing on the persecution of Christians by the Roman Catholic Church.
