surprised no one has done this yet: here's all previous versions of question asked here with good responses that i found

https://www.reddit.com/r/AskHistorians/comments/3rb6y5/a_small_splinter_group_of_the_muslim_army_crossed/

https://www.reddit.com/r/AskHistorians/comments/1uce2a/how_viable_was_an_umayyad_occupation_of_france/

https://www.reddit.com/r/AskHistorians/comments/2rjwgb/were_the_kingdoms_in_europe_ready_both/

there are some solid answers but there is room for a more