Simple Answer:
The Muslims (often called Moors incorrectly -- see complex answer) invaded Spain and ruled over parts of the Iberian Peninsula from 711-1492. The Jews were not an active part of the conquest force or the militaries raised by either the Muslims, but they were a significant part of the civilian population within the Muslim-controlled regions of Spain.
Complex Answer:
What is a Moor?
The proper term for the "Moors" is "AMAZIGH", as they are known in their language, or "Berbers" as both Westerners and Arabs have identified them. Amazigh are the indigenous people of the Maghreb or northwest Africa (Morocco, Algeria and Tunisia.) Amazigh come in nearly every color, from pale white skin to dark black skin. They had recently converted to Islam when Arab Islamic Armies had barrelled their way across North Africa. The Amazigh were the primary military force involved in overrunning Visigothic Catholic Spain and the lead Muslim general, Tariq ibn Ziyad, is commonly believed to be Amazigh.
Other Muslim Groups in Spain
However, in addition to the Amazigh, there were numerous significant minorities of Muslims who lived in Spain. The largest minority were ARABS or Muslims coming from Middle East. They were a mix of people from Arabia, the Levant, Mesopotamia, and Egypt. Arabs were actually the rulers of all of Islamic Spain from 711-1038 C.E., the Umayyad Caliphate, after which the Amazigh became much more powerful and prominent, especially with the Almoravid and Almohad Caliphates. However, the last Islamic nation in Spain was the Arab Nasrid Emirate of Granada, which existed alone from 1252-1492.
Another major group were the MULADIS who were indigenous Iberians/Spaniards who converted to Islam. Muladis very rarely wielded political power and were often taxed as Non-Muslims, but there were occasions when they were able to gain power in the Taifa Kingdoms, which were Islamic city-states in southern Spain which developed after the fall of Umayyad Caliphate of Cordoba, but before the Almoravid invasion and again after the Almohads were excised from Spain, but before the Christian North conquered all of them save the Emirate of Granada.
The last major group of Muslims in Spain were the former Slavic Slaves called SAQALIBA. The Muslims had a massive slave trade throughout the Mediterranean and Eastern Europe (as well as with Sub-Saharan Africa). One of the largest places of origin for Islamic Slaves was southeastern and eastern Europe, where numerous Slavic peoples were sold into slavery. Many of these Slavs became slaves in Islamic Spain. However, some were able to earn their freedom, usually by a combination of luck, physical ability to overpower their master, and conversion to Islam. These now-freed Slavs who had been born in Spain and were now Muslims were called Saqaliba. Saqaliba very rarely wielded political power, but there were occasions when they were able to gain power in the Taifa Kingdoms (like the Muladis). The Saqaliba famously ruled the Taifa of Denia, which controlled parts of the Balaeric Islands and Valencia.
What was the Jews' Involvement in Islamic Spain
By most accounts, the Iberian Jewish community was in favor of the Islamic Conquest of Spain. Muslims were believed (correctly) to be more tolerant of Jews and Jewish practice than the Catholic Visigoths currently in power over them. As a result, local Jews assisted Muslims in their conquests throughout Spain. A great example of this was when the Muslims captured the city of Cordoba. They approached the Jewish community, gave them weapons, and asked them to be the stewards of the city until the Conquest of Spain was complete. The Jewish community maintained Law and Order in Cordoba for two years until the conquest of Spain was more-or-less complete and the Muslim leadership returned to the area and confiscated the weapons they had previously given the Jews. From that point forward, Jews were forbidden the right to self-defense.
Once this period of conquest (711-714) was over, Jews primarily contributed to Islamic Spain through artisanry, poetry, science, and philosophy. Jewish intellectuals participated in the Islamic Golden Age in Spain as did Mozarab Christians. It must be made clear that while Jews in the Umayyad Caliphate had many more privileges than Jews outside of the Caliphate, these are nowhere near commensurate to the rights that Jews enjoy in Western countries today. For more information on the treatment of Jews under Islam, please see the Related Question: What was the treatment of non-Muslims under Muslim rule?
Related Q&A：
Did Jews and Moors try to take over Spain？-Well, the history is a bit more complex than a simple yes or no. The Moors did have a significant presence and influence in parts of Spain for a considerable period of time. They brought with them advanced knowledge and cultural contributions. But to say they were trying to \take over\ Spain outright might be an oversimplification. As for the Jews, they were an important part of Spanish society, but not in a way that suggested they were attempting to seize control of the entire country. It's important to look at these historical events in a nuanced way and understand the context and various factors at play.
