Is Italian is an Indo-European language?
Of course, given that travel was difficult back then, and rapid electronic communication non-existent until quite recently in history, over time the Latin language changed a bit in each area, and the many varieties developed over the centuries into distinct languages with many differences in grammar, pronunciation rules, and vocabulary. What we call the Italian language is one of those many variants or dialects of what developed on the peninsula today called the nation of Italy. Modern-day Spanish, French and Portuguese (and several other modern languages) are morphed or changed forms of the old Latin language. Hence all of these are part of the Indo-European languages by virtue of their descent from that older Latin language.