Following the cave-dwellers and hunter-gatherers of the Peleolithic Age, as well as the subsequent Iberian (in the south) and Celtic (in the north) tribes who settled throughout the peninsula, the Phoenicians were the first great "civilization" to make their mark on early Spanish history. Spain saw its first days as an important trading post with both the Phoenicians and Greeks, while the following inhabitants - the Carthaginians - essentially set foot on the peninsula aiming to expand their growing empire.
Eventually, the ever-ambitious Roman Empire stepped in. However, it was no easy task. It took nearly two centuries to quelch the resistance of the Celtiberian tribes that still inhabited the bulk of the country. In fact, the Basques, who have a history of "doing their own thing," never completely Romanized like the rest of Spain. Under the Romans, Spain flourished and even became the Roman Empire's second most important nucleus, just a notch under Italy itself.
However, what goes up generally comes back down- and so it was with the Roman chapter of early Spanish history. Following a brief Golden Age which saw the construction of buildings, roads and bridges, inner strife and the decadence of the Roman Empire in the 5th century opened up the opportunity for the Visigoths to take charge.