With the collapse of the Rhine frontier (CE 406), barbarian peoples forced their way into Gaul and crossed the Pyrenees.  A Germanic tribe, the Suebi, was settled in southern Galliaecia, their rulers residing at or near Bracara Augusta (Braga) and Portucale (the future Oporto).  They annexed Lusitania and for a time overran the rest of the peninsula, but the Visigoths were sent to subdue them and extinguished their monarchy (CE 469).  The records are silent until c. 550, when the Suebi monarchy had been restored and was reconverted to Catholicism by St. Martin of Braga.  St. Martin’s church grouped together the bishoprics of the Suebic territory until c. 660.   

History is also silent about this period in Chaves, except for one minor light breaking through in the documents left by a bishop called Idacio.  The declining thermal city seems to have been the seat of a bishopric, of short duration, and with only one bishop, Idacio (427 CE), of Limia, author of the Chronicon, one of the few documents telling us about the history of the times.  Frumario, a Visigothic king who devastated the town, probably in the wars against the Suebians, made Idacio prisoner.  Although freed and allowed to return to his church, which had been badly damaged, he could not stop the temple from being destroyed later, putting an end to the bishopric of Chaves.  

The Muslim Invasion and the Reconquest(after 711)

The next violent change in the fortunes of Chaves was the period of unrest following the Muslim invasion of 711.  After the disastrous battle of Guadalete in Spain, the Islamic wave, spreading out through Spain, by the end of the first quarter of the eighth century had finally reached the edge of the mountains of Galicia.  Orense was actually destroyed.  Aquae Flaviae must have had a similar fate (we have no records), and probably stagnated obscurely in ruins for about one century.   

In 888, in the reign of Afonso III of Leon, it was re-conquered.  Handed over to the first Count of Portugal, Henry of Burgundy, as part of the dowry for his marriage to Teresa,the bastard daughter of the Leonese king, Chaves once more fell into the hands of the Moors, this time in 1129.  Finally in 1160,on the initiative of two brothers Rui and Garcia Lopes, it was seized from the Moors and given, as a present, to Portugal’s first king, Afonso Henriques.  According to the legend, this king, in recognition of the brothers' feat, gave them the privilege of using five keys on their coat of arms, these keys corresponding to five gates in the walls of the Chaves fortress.  As a consequence the brothers were supposed to have taken on the name of Lopes de Chaves.  Some historians now think that these stories are mixtures of events that took place much later and that the brothers were not even Portuguese but Castilian from Ciudad Rodrigo.  And they were not fighting the Moors but fellow Christians.  We will probably never find out the truth. 

At this time the area around Chaves must have been sparsely populated, as a consequence of the frequent destructive incursions, which the Moors as well as the Leonese and Asturian Christians frequently carried out.  A large part of the area would have been a kind of burnt no-man's land.  Several towns, which two centuries later would have a relative importance, did not even exist.  For example:  Miranda do Douro, Mirandela, and Vila Real, now the district capital and larger than Chaves.  

The first Portuguese king rarely must have travelled through this territory.  His unstoppable will to fight and expand his kingdom took him further south.  Chaves was no longer important since it was now safely in the hands of the Portuguese monarchy.  The true struggle lay further south in the rich populated areas of southern Portugal, which were coveted by others like the Moors.  Chaves was useful only as a fortification if the Spanish decided to come south.  This they did quite often, and quite often the town must have been razed to the ground.   

Struggles with Castilla

Once Chaves was freed from the Moors it enjoyed only a short period under Portuguese rule.  Lying so close to the border it was subject to frequent raids from the north.  During the reign of Afonso II in 1212, when some Portuguese were participating in the battle of Navas de Tolosa against the Moors, the forces of Afonso IX of Leon again occupied Chaves.  This captivity lasted for 19 years, since only during the reign of Sancho II, did it return to the Portuguese crown. 

In 1253 Afonso III, king of Portugal, came to Chaves to marry Beatriz, daughter of the king of Leon and Castille, Afonso X, the Wise.  Five years later, the town received its first charter.  During the next years the town was reinforced with defensive walls, and the castle was built, a replica of the powerful Galaico-Leonese fortress of Monterrey, not far away.  A distance of twenty-five kilometres separated the two and on a clear day the castle of Monterrey can be easily seen from any hill in Chaves.  The two castles were destined to be the victims of assault and siege.  Chaves, being on the weak end of the stick, would see its share of attacks coming from the direction of Monterrey.  But the opposite never occurred.  Never did the Portuguese have the force to lay siege to Monterrey.

A well-preserved steet in old Chaves (photo from Câmara Municipal de Chaves: Guia do Munícipe )

  History of the Municipality 

The first medieval municipality in the region was Couto de Ervededo, with its seat in the village that would later have the present-day name of Torre.   Donated to the archbishop of Braga by Teresa, Afonso Henrique’s mother, this territory was an ecclesiastical lordship.   It received its carta de foro (charter) in 1238.  A small castle was built with a keep, in which was located the administrative, military, and judicial life of the concelho.   This tower was later burned and destroyed in the border incursions of 1641.  Curiously, this concelho on the frontier changed nationality several times throughout history, being Galego, Leones, Portuguese and Castilian.  Now completely Portuguese, it was absorbed into the concelho of Chaves when that of Ervededo was extinguished in 1853. 

During the same period, on the other side of the Tâmega, in Santo Estevão, the concelho of Santo Estêvão de Chaves was created in 1258.  The government had chosen to locate here due to the decadence in which the town of Chaves had fallen.  Chaves was at the time almost deserted. 

At the end of the thirteenth century Chaves took on new life, especially when it received a charter from King Afonso III in 1258.  Slowly the town began to be populated again and the castle reconstructed.  After this Santo Estevão would lose its autonomy and become integrated into the concelho of Chaves. 

In 1350 Afonso IV renewed all the privileges conceded to Chaves by way of a new foral or charter. 

Chaves supports Castile--1385 

During the struggle between Portugal and Spain in 1385 Chaves was the stronghold of the forces that opposed the new king, John I, who had defeated the Spanish at Aljubarrota.  At the time the town belonged to the crown, and this was to determine the position of its alcaide (mayor) in the dynastic crisis.  The alcaide had taken an oath to defend Beatriz, wife to John I of Castile and heiress to the crown of Portugal after the death of Ferdinand (1367-83), the last of the House of Burgundy, founded by Henry of Burgundy. John, together with his trusted ally, Nuno Alvares Pereira, “the Holy Constable,” personally led his troops to besiege the town; the resistance lasted four months.  Incredibly the Portuguese king granted the rebel a treaty of forty days so that he could send a letter to the king of Castile asking for help or, if it was not forthcoming, to free him from his oath of loyalty.  The king of Castile, although impressed with the loyalty of the mayor, sent back that he could not help and that he was freeing him of his sworn oath. Since the help never came and the town did not have springs inside the walls, Chaves was forced to surrender.  With an uncommon display of fair-play the mayor and his forces were allowed to make their way north to Monterrey.   

The lordship of the town was then bestowed on Nuno Alvares, the most important noble of the land. Alvares then included the town in the dowry of his daughter, Beatriz, when she took Afonso, illegitimate son of John I in marriage.  The marriage took place in Chaves. Afonso, who was already the count of Barcelos now became the first Duke of Braganza; thus Chaves became part of the House of Braganza, to which it belonged for centuries.  The dukes lived here and shortly after Beatriz was to die here.  Today we can see the Palace of the Dukes of Braganza and a statue of Afonso in the main square in the city centre.