During the 7th and 8th centuries, Islam expanding out of the Arabian Peninsula, across southwest Asia, and across North Africa.
As shown in this map, by beginning of the 8th century (711 CE) Islamic movement into Europe had begun, moving northward until their 732 CE defeat at Tours and Poitier.
Age of Caliphs By United States of America federal government (http://www.gl.iit.edu/govdocs/maps/maps.htm) [Public domain], via Wikimedia Commons
After Muhammad’s death, the Islamic Empire was governed by a series of Caliphs, or political leaders. Later, there would be divisions within the lands controlled by Islamic leaders but for a brief time, this was a massive, unified empire.
These documents illustrate two episodes in the initial Islamic incursion into Europe.
Tariq ibn Ziyad addresses his troops
Ibn Abd-el-Hakem on the Conquest of Spain