What did muslims scholars do that allowed for the spread and preservations of knowledge?

From the 11th to 13th centuries, medieval Europe absorbed knowledge from Islamic civilization, which was then at its cultural peak. Of particular importance was the rediscovery of some ancient classic texts, most notably the work of the Greek natural philosopher Aristotle, through retranslations from Arabic. Also of note is the reception of advances in astronomy and mathematics made in the Islamic world during the 10th century, such as the development of the astrolabe.

An example of a political opponent would be albert einstein hitler hated him because he was jewish a pacifist