Latin was the main language of government and administration in the Western Roman Empire.
Roman officials used Latin for laws, military orders, public inscriptions, and much of state correspondence in the western provinces. It spread through the army, colonies, courts, and administrative institutions, helping connect communities across a vast territory.
Greek remained extremely important, especially in the eastern Mediterranean. It was widely used in cities, education, trade, philosophy, and Christian writing. The Eastern Roman Empire continued to use both languages for centuries, and Greek eventually became its dominant official language.
Latin did not replace every local language. Celtic, Punic, Egyptian, Aramaic, and other languages continued in different regions. Over time, spoken regional forms of Latin developed into Romance languages such as Italian, French, Spanish, Portuguese, and Romanian. Classical Latin and everyday spoken Latin were related but not identical varieties.