To reinforce this thesis we rely on sources of Latin authors such as Polybius ( X 38 , 7 to 40 ) when it states that " The Carthaginian general then toured the sites of Cástulo , around the city of Becula , not far from its mines silver. Informed of the proximity of the Romans, moved his camp [ ... ] " ( Polybius X 38 , 7 ​​and 8). And Livy, which confirmed this information and added some data more " next Carthaginian army, Hasdrubal was near the city of Becula . Before the camp had cavalry outposts ; the escaramuceadotes , the frontline troops and who were at the head of the column, (referring to the Roman army ) on the fly , and before looking for the camp site , launched an attack against them taking them seriously so little that there was questions about what was the moral one and the other side , the riders were rejected in a hasty escape to the camp , and the Roman ensigns came almost to the gates . That day just fighting spirit flared and Romans encamped " ( Livy XXVII 18 , 1-4 ).

Surely pressured by these actions change Asdrubal camp to a place that Polybius had " [ ... ] a river that flowed behind and in front of the stockade was a plain defended by a rock deep enough to provide protection ; the plain was so wide that it fit in the Carthaginian army formed . Hasdrubal stood on this site ; bet sentries day and night on the reef " ( Polybius X 38 , 8) . And Livy describes it as follows : "At night , Hasdrubal withdrew its troops at a height that was an esplanade on the top. Behind was a river in front and the sides all the way around it clung kind of steep embankment . At the bottom there was another slightly inclined plain , surrounded in turn by an equally hard to climb ledge. When the next day I saw Hasdrubal the Roman army was formed before the camp , brought down to this lower plain these Numidian horsemen and African Balearic and light weapons " ( Livy XXVII 18 , 5-7 ).

Said the geographic references can relate with Rumble Guadiel and rivers and the Jarosa and Navarra hills disappeared today.

Famed archaeologist Schulten would corroborate these theories.

Subsequently Baecula name appears also related to subsequent Civil Wars of Rome. Hirtuyelo, Sertorius's lieutenant, is defeated by Metellus in Baecula-Andalusia. Julius Caesar overnight in this city before the battle of Munda, where he defeated Pompey's sons.

The early Christian Visigoth past and our venerable town little is known only reference a small Visigothic monastery bent (divided by nuns and monks), it treats the registration of a foundation stone in the walls of the old church of San Andres and Santa Gertrudis, early patrons of Bailen, whose drain is in the Archaeological Museum of Madrid, in the absence of the original, which reads:

Abbot ... Locuber founded and built this monastery two choirs in 691, during the reign of the Visigoth king Égica ...

The date would match the 14 May, the day of Bailen.

Almost zero, are the vestiges we have of Andalusian past of our city, except the intuition of the name "Baylen" may well come from the Arab past that precedes us, as it is not mentioned in the sources except on one occasion, when in 1155 Alfonso VII gave the castles of Bathrooms, Segral Baylen and his vassal Abdelaziz in Baeza. This time we just reference the castle and a mosque built between 860 and 880 by Abd al-Rahman I on the old Visigothic monastery.

With the Christian reconquest, Baylen became realengo land, property of the Castilian kings from 1227 and dependent Baeza council and its Jurisdiction, as evidenced by a document of 1331, (the time of Fernando III "The Saint") appearing our villa connected between the parishes belonging to Baeza.

In 1349, the Castilian King Alfonso XI, reward his vassal Pedro Ponce de León, Lord of Marchena, for their assistance in making Gibraltar plaza allows you to shop for the term of Baylen and his castle in the amount of 140000 maravedíes, becoming manor land now.

So Baylen Castle went on to become a key player.

Throughout the fifteenth century we have several news Castillo de Bailen, now disappeared, appearing to related Constable Lucas Iranzo and this when 1459 was going to settle in Jaén, a plague in this city led him to provisionally set Bailen. In Bailen spent nearly eleven months dedicated to organizing parties and hunt in the environment.

In the late fifteenth century begin, territorial disputes with the neighboring city of Baeza, which claimed for itself the land neighboring village of Baylen. The issue was resolved by a judgment of Ferdinand, 1504, by which would Baylen expanded its territory at the expense of an annual tribute payable to Baeza to be maintained until the last third of the nineteenth.