In the linguistics of the Romance languages, the La Spezia–Rimini Line, also known as the Massa–Senigallia Line, is a line that demarcates a number of important isoglosses that distinguish Romance languages south and east of the line from Romance languages north and west of it. The line divides northern and central Italy, running approximately between the cities of La Spezia and Rimini (or, according to some linguists, between Massa and Senigallia, which lie about 40 kilometres further to the south). Romance languages south and east of it include Italian and the Eastern Romance languages (Romanian, Aromanian, Megleno-Romanian, Istro-Romanian), whereas Catalan, French, Occitan, Portuguese, Romansh, Spanish, and the Gallo‒Italic languages are representatives of the Western group. In this classification, the Sardinian language is not part of either Western or Eastern Romance.
It has been suggested that the origin of these developments is to be found during the last decades of the Western Roman Empire and the Ostrogothic Kingdom (c. 395–535 AD). During this period, the area of Italy north of the line was dominated by an increasingly Germanic Roman army of (northern) Italy, followed by the Ostrogoths; the Roman Senate and Papacy became the dominant social elements south of the line. As for the provinces outside Italy, the social influences in Gaul and Iberia were broadly similar to those in northern Italy, whereas the Balkans were dominated by the Byzantine Empire at this time (and later, by Slavic peoples). In either case, it coincides approximately with the northern range of the Apennine Mountains, which could have helped the development of these linguistic differences.
