The Chassidei Ashkenaz (literally the Pious of Germany) was a Jewish movement in the 12th and 13th century founded by Rabbi Judah the Pious (Rav Yehuda HaChassid) of Regensburg, Germany and several other German Jews.

Rabbi Judah was bron in Speyer, Germany in 1150 during at a time of persecution for Jews. He was a Tosafist and attended the schools of the Tosafists. At a young age though he came to learn under his father Rabbi Samuel (Rav Shmuel HaChassid) who taught him the intricate words of the Kabbala. Rabbi Judah soon became a renown and famous Kabbalist. He with his father and several other German Jews took upon themselves an oath of piety and became purely pious men. They were known throughout the German lands and many flocked to learn from them. One can see how the felt on different matters when reading prominent Chassidei Ashkenaz works. Classics are the Sefer HaChassidim by Rabbi Judah and Rabbi Judah's famous liturgal poem Anim Zemirot which is recited every Sabbath in Ashkenazic Synagogues. Another classic is Rabbi Elazar Rokeach's work Sefer HaRokeiach. Rabbi Rokeach's student was Rabbi Moses ben Nachman commonly known as Nachmanides who wrote a famous commentary on the Torah. The Chassidei Ashkenaz would not last though. Due to extreme persecution a great number of the Chassdei Ashkenaz migrated to Spain during the early part of the 13th century. After Rabbi Judah passed away in 1217 and the Rindfleish Massacres in the early part of the 13th century almost all the Chassdei Ashkenaz moved out of the Germanic lands. The ones that came to Spain simply just changed their movement's name and they and their students became the great Kabbalists of the Jewish Golden Age in Spain in the 13th century. The remaining Chassidei Ashkenaz vanished from history after they died. By the onset of the 14th century the movement no longer existed. Even so the Chassidei Ashkenaz had a great effect on the world Jewry. To this day many Orthodox Jews learn the works of the Chassidei Ashkenaz.