I ask this question because I was thinking about some of the ways the English language was influenced (such as the Vikings), and it made me wonder this. For a long time in the Middle Ages, Iberia was controlled by various Islamic realms and groups, such as the Moors, and I’m sure their languages would have been different from Spanish or other Latin-derived languages, and given how long Muslims controlled Iberia, there had to be some kind of influence, right?
Yes, there was influence largely in vocabulary and some adaption of Arabic phonetics to the habla romance used across Iberia. Lapesa’s 5th chapter “Los árabes y el elemento árabe en el español”, has detailed coverage about Arabic influence on the development of Spanish. In general though, the Arabic influence is most pronounced in nouns related to warfare (jineta comes to mind), agriculture (alcachofa, zanahoria, alfalfa, azúcar, algodón amongst many others) commerce (almacén, aranceles, tarifa, aduanas), government (aldea, alcalde), sciences (álgebra, cifra) and other fields. Not that many adjectives were incorporated, often colors like azul and carmesí. Nor many verbs, though the commonly used “ojalá que” is derived from Arabic.
For detailed phonetic discussion of changes of Arabic sounds to those that were adapted by Spanish, like palatalization of /k/, /ll/, /nn/, again see any of the listed sources, below. Vowels were definitely altered and is evident with diphthongs like the change from Arabic* al-daia* to Spanish aldea.
Lapesa, Rafael. Historia de la lengua española. Madrid : Editorial Gredos, 1980. Has been reprinted and revised numerous times.
Penny, Ralph. A History of the Spanish Language. 2nd Ed. New York: Cambridge UP, 2002
Pharisee, David. Breve historia de la lengua española: Segunda edición revisada. Chicago: U of Chicago Press, 2015.