answer: there has been a history of anti-Jewish hatred and attacks in Muslim lands against Jews but also times of "golden ages" where Jews were somewhat left alone (although they were 2nd class citizens) - this happened before, during and after the crusades.
Pact of Umar, circa 720: Jews and Christians as second class citizens in Muslim countries. Give up a seat to a Muslim, rise when a Muslim enters * conversion to Christianity or Judaism illegal * no raising of voices at funerals * no riding on horses and no saddles
Further restrictions came over time: ridiculous clothing * walking on the left of any Muslim * out of the way synagogues * required to pay a fine to remain Jewish or Christian.
807 – All Jews in the Caliphate of Abbassid to wear a yellow belt, Christians a blue one.
1016 – Tunisia – Jews are forced to convert or leave.
1066 – Granada – a Muslim mob storm the palace and crucify the Jewish vizier and massacre most of the Jewish population. 4,000 die.
1090 – Granada – Jews again attacked.
1107 – Moroccan Jews ordered to convert or leave.
1146 – Jews in Morocco again ordered to convert to Islam or die, thousands fled, the majority were executed.
1148 – 1212 – Granada – Jews forced to convert to Christianity or Islam.
1165 – forced conversions in Yemen.
1190 - Saladdin takes over Jerusalem from Crusades and lifts the ban for Jews to live there.
1232 - Forced mass conversions in Marrakesh.
1333 - forced mass conversions in Baghdad
1435 - Massacre and forced conversion of Marjorcan Jews.
1438 - Establishment of mellahs (ghettos) in Morocco.
1619 - Shah Abbasi of the Persian Sufi Dynasty increases persecution against the Jews, forcing many to outwardly practice Islam. Many keep practicing Judaism in secret.
1790-1792 - Destruction of most of the Jewish communities of Morocco.
1805 - Massacre of Jews in Algeria.
1840 - The Damascus affair: false accusations cause arrests and atrocities, culminating in the seizure of sixty-three Jewish children and attacks on Jewish communities throughout the Middle East.
1921 May 1-4 – Jaffa riots in Palestine.
1929 August 23 - The ancient Jewish community of Hebron is destroyed in the Hebron massacre.
1934 - 2,000 of Afghani Jews expelled from their towns and forced to live in the wilderness.
1941 - The Farhud pogrom in Baghdad results in 200 Jews dead, 2,000 wounded.
WWII – Muslims served in the Waffen-SS in the Handschar units in the Middle East and the Balkans hunting down partisans and Jews for the Nazis. Their German officers wore fez hats with the swastika. The uniform insignia included the swastika and a scimitar
1948-2001 - Antisemitism played a major role in the Jewish exodus from Arab lands. The Jewish population in the Arab Middle East and North Africa has decreased from 900,000 in 1948 to less than 8,000 in 2001.
1948 - During the Siege of Jerusalem of the Arab-Israeli War, Arab armies were able to conquer the part of the West Bank and Jerusalem; they expelled all Jews (about 2,000) from the Old City (the Jewish Quarter) and destroyed the ancient synagogues that were in Old City as well.
1968 - The ancient Jewish community of Hebron, which had been destroyed in the 1929 Hebron massacre, is revived at Kiryat Arba. The community, in 1979 and afterwards, moves into Hebron proper and rebuilds the demolished Abraham Avinu Synagogue, the site of which had been used by Jordan as a cattle-pen.