The term "Gallo-Roman" refers to the cultural and historical period in ancient Gaul during the Roman Empire, characterized by the blending of Roman and Celtic traditions. This fusion occurred after the Roman conquest of Gaul in the 1st century BCE, leading to the adoption of Roman customs, language, and governance by the local populations. Gallo-Roman society is marked by advancements in architecture, art, and urban planning, with cities like Lyon and Nîmes showcasing Roman influence. The period also saw the spread of Christianity, which further shaped the cultural landscape of the region as it transitioned into the Middle Ages.