Although we can identify a classic period of the language and Rome had institutions to preserve and promote a standard, there was probably never a universal Latin spoken across the Empire.
Romance languages descended from Latin but as conquests of Gaul, Iberia and the Balkans came centuries apart, the spoken language that supplanted their native tongues had changed as well. Early on during the Punic Wars as the Empire was expanding across the Mediterranean, Rome secured the lands of Spain from Carthage, and through the discontinuity of the French speakers, Spain remains one of the vulgar languages most true to that original language. Euskara, the language of the Basque people, seems to have developed prior to the arrival of Indo-Europeans and has endured to modern times. The subjugation of the Gallic tribes came later, after Rome had absorbed Greece and Macedonia and incorporated many Greek words, reflected in modern French. Of course, other powers came to dominate these provinces as Rome’s influence waned and these Germanic speakers helped shape the vernacular dialects to a greater or lesser extent. Owing to the Franks, French has inherited a smattering of Germanic loan-words.
The Visigoths, however, who came to rule the Iberian peninsula, due to extended contact with the Roman civilization, were bilingual in Latin and Gothic, and Latin and its derivative local languages remained in common-parlance for day-to-day activities and native Gothic remained mostly in the background. Exceptions were found in the Church, Gothic having been the first Germanic language to be written down in order to produce that Gothic Bible commissioned by the Arian bishop Ulfilas, until the Roman Catholic Church consolidated authority, and interestingly in family names to this day. Many of the most common surnames of Spain, Portugal and Latin America reflect remnants of Visigoth rule: Hernรกndez from Ferdinand (protector of the peace and probably a title rather than a name originally), Gutiรฉrrez from Walter—wielder of hosts, Rodrรญguez, son of Roderik, the name of one of the last kings of the Goths before the Muslim incursions into the area and meaning rich in glory.