Well poisoning in the context of "1948 Palestinian expulsion and flight"

The First Sacred War, or Cirraean War, was fought between the Amphictyonic League of Delphi and the city of Kirrha. At the beginning of the 6th century BC, the Pylaeo-Delphic Amphictyony, controlled by the Thessalians, attempted to take hold of the Sacred Land (or Kirrhaean Plain) of Apollo, resulting in this war. The conflict arose due to Kirrha's frequent robbery and mistreatment of pilgrims going to Delphi and their encroachments upon Delphic land. The war, which culminated with the defeat and destruction of Kirrha, is notable for the use of chemical warfare at the Siege of Kirrha, in the form of hellebore being used to poison the city's water supply. The war's end was marked by the organization of the first Pythian Games.

The history of the Jews in Germany goes back at least to the year 321 CE, and continued through the Early Middle Ages (5th to 10th centuries CE) and High Middle Ages (c. 1000–1299 CE) when Jewish immigrants from France founded the Ashkenazi Jewish community. The community survived under Charlemagne, but suffered during the Crusades. Accusations of well poisoning during the Black Death (1346–1353) led to mass slaughter of German Jews, while others fled in large numbers to Poland. The Jewish communities of the cities of Mainz, Speyer and Worms became the center of Jewish life during medieval times. "This was a golden age as area bishops protected the Jews, resulting in increased trade and prosperity."

The First Crusade began an era of persecution of Jews in Germany. Entire communities, like those of Trier, Worms, Mainz and Cologne, were slaughtered. The Hussite Wars became the signal for renewed persecution of Jews. The end of the 15th century was a period of religious hatred that ascribed to Jews all possible evils. With Napoleon's fall in 1815, growing nationalism resulted in increasing repression. From August to October 1819, pogroms that came to be known as the Hep-Hep riots took place throughout Germany. During this time, many German states stripped Jews of their civil rights. As a result, many German Jews began to emigrate.

Operation Cast Thy Bread was a top-secret biological warfare operation conducted by the Haganah and later the Israel Defense Forces which began in April 1948, during the 1948 Palestine war. The Haganah used typhoid bacteria to contaminate drinking water wells in violation of the 1925 Geneva Protocol. Its objective was to frighten and prevent Palestinian Arabs from returning to villages captured by the Yishuv and make conditions difficult for Arab armies attempting to retake territories. The operation resulted in severe illness among local Palestinian citizens. In the final months of the 1948 Arab–Israeli War, Israel gave orders to expand the biological warfare campaign into neighboring Arab states such as Egypt, Lebanon, and Syria, but they were not carried out. Israeli prime minister David Ben-Gurion and IDF chief of general staff Yigael Yadin oversaw and approved the use of biological warfare.

Abba Eban, representative of the Jewish Agency for Palestine, strongly denied the operation and sought to block further investigations by accusing the Arab states of engaging in "antisemitic incitement". Operation Cast Thy Bread did not achieve the crippling effects its advocates had hoped for, and was discontinued by December 1948. In July 1948, the Palestinian Arab Higher Committee reported to the United Nations several war crimes committed by Zionist forces, including the use of "bacteriological warfare".

Blood libel or ritual murder libel (also blood accusation) is an antisemitic trope which falsely accuses Jews of murdering Christians in order to use their blood in the performance of religious rituals. Echoing very old myths of secret cultic practices in many prehistoric societies, the claim, as it is leveled against Jews, was rarely attested to in antiquity. According to Tertullian, it originally emerged in late antiquity as an accusation made against members of the early Christian community of the Roman Empire. Once this accusation had been dismissed, it was revived a millennium later as a Christian slander against Jews in the medieval period. The first examples of medieval blood libel emerged in the Kingdom of England in the 1140s, before spreading into other parts of Europe, especially France and Germany. This libel, alongside those of well poisoning and host desecration, became a major theme of the persecution of Jews in Europe from that period down to modern times.

Blood libels often claim that Jews require human blood for the baking of matzos, an unleavened flatbread which is eaten during Passover. Earlier versions of the blood libel accused Jews of ritually re-enacting the crucifixion. The accusations often assert that the blood of Christian children is especially coveted, and historically, blood libel claims have been made in order to account for the otherwise unexplained deaths of children. In some cases, the alleged victims of human sacrifice have become venerated as Christian martyrs. Many of these – most prominently William of Norwich (1144), Little Saint Hugh of Lincoln (1255), and Simon of Trent (1475) – became objects of local cults and veneration; the cult of Hugh of Lincoln gained the support of Henry III and his son Edward I, giving it official credibility and helping it to be particularly well remembered. Although he was never canonized, the veneration of Simon was added to the General Roman Calendar. One child who was allegedly murdered by Jews, Gabriel of Białystok, was canonized by the Russian Orthodox Church.