Their development was halted by the Roman expansion in the Po Valley from the 3rd century BC onwards. After centuries of struggle, in 194 BC the entire area of what is now Northern Italy became a Roman province with the name of Gallia Cisalpina ("Gaul on the inner side (with respect to Rome) of the Alps"). The Roman culture and language overwhelmed the former civilization in the following years, and Northern Italy became one of the most developed and rich areas of the western half of the empire with the construction of a wide array of roads and the development of agriculture and trade.