The castle site of Montbazon comprises a series of fortified structures situated within the French commune of Montbazon, located in the department of Indre-et-Loire and the Centre-Val de Loire region.
The site overlooks the Indre valley and controls both land and river routes. The development of the site is believed to have begun in the late 10th or early 11th century with the construction of a keep (donjon), which is generally attributed to Fulk Nerra. This development occurred at the edge of a rocky promontory that overlooked the valley. The tower construction was part of the power struggle between the houses of Blois and Anjou in this part of Touraine. Subsequently, the tower was augmented with the construction of an outwork, a curtain wall, and two enclosures, which were erected to safeguard the entire site. These additions were made for several centuries, from the early 11th to the 15th century. A Renaissance castle was constructed in the 15th century, and notable figures (Louis VII, Louis XI, Catherine de' Medici, and Henry of Navarre) resided there for varying periods. However, the castle was ultimately destroyed a little more than three centuries later due to extensive dilapidation while uninhabited. The seigniorial chapel and a portion of the enclosure also suffered a similar fate.
Since the French Revolution, modifications and restorations have been carried out by successive owners, notably from 1922 to the late 1950s and the Atterton couple in the 2000s. However, most modifications and restorations were carried out from the 20th century onwards. In the 21st century, the keep, which still stands at a height of 28 meters, remains the most significant feature of this site open to the public. However, the ongoing collapse of the hillside is causing concern due to its potential impact on the stability of the promontory's edge and the houses constructed on the lower slopes.
The keep was initially designated a historic monument by a decree on 28 October 1926. Subsequently, on 24 May 2012, the protection was extended to encompass the entire castle site, which has been accessible to the public since 2003. A subsequent classification decree of 11 May 2024, replaced the 1926 listing.
Location
The castle site is located on a promontory fort in the commune of Montbazon, in the French department of Indre-et-Loire. The site is protected on two sides by the valleys of the Indre and the Gironde, which together form a small temporary tributary that also serves as the moat for the town's enclosure.
This location enables the regulation of the Indre crossing by the Tours-Poitiers road, situated at the foot of the promontory, and the river navigation. Subsequently, a village emerged at the foot of the promontory on the left bank of the river, which was soon complemented by a suburb on the right bank, situated between two arms of the Indre. In the 10th and 11th centuries, Montbazon was in a geographically strategic area coveted by both the Counts of Anjou and the Counts of Blois. The construction of a chain of fortresses was intended to allow the former to secure control over all of Touraine. In this respect, Montbazon, approximately ten kilometers from Tours on the road leading south to France, was ideally located.
History
Studies and research
In the 16th century, the construction of the keep was attributed to Julius Caesar. At that time, large ancient constructions were generally considered the work of a powerful and prestigious civilization, that of the Romans, personified by its most famous representative. One of the first studies tracing the history and archaeology of the keep was published by Louis Bousrez in 1895 in Bulletin de la Société archéologique de Touraine.
In 1969, medieval historian Marcel Deyres provided a precise description of the keep's structures in the . This study allowed him to propose a construction timeline for the fortress. However, ten years later, Bernard Bachrach challenged the hypothesis of an original wooden keep built on a mound, which had been suggested by Deyres.
In 2002, fortification historian Nicolas Faucherre published a lengthy article in the Bulletin des amis du pays lochois, wherein he advanced novel hypotheses regarding the construction chronology of the entire castle site (keep and adjoining structures). However, he acknowledged that his conclusions represented primarily research avenues that did not integrate the findings of ongoing university studies.
The latest research on the castles at Loches (dendrochronological studies) and Langeais, comparable to Montbazon, and the of the Montbazon castle site conducted by Marie-Denise Dalayeun from 2002 as part of her academic work have enabled the formulation of a revised construction timeline for the site and a new interpretation of the functionality of the various buildings. These findings challenge and replace the conclusions of earlier studies. The same archaeologist continued her excavations and investigations until 2015..
Although the relative chronology of the site (the order of successive construction or remodeling phases) appears to be well-established, the absolute chronology (precise dating of these phases) remains to be defined, particularly for the medieval period, which is poorly documented by written sources. The proposals put forth remain open to discussion. These uncertainties are also linked to the numerous repair and restoration campaigns that affected the keep in particular, resulting in the erasure of part of its ancient structures. Furthermore, the lack of wooden remains at Montbazon precludes the possibility of employing a dendrochronological approach.
10th and 11th centuries: Birth of the castle complex
Towards the end of the 10th or early 11th century, a multitude of defensive structures were erected in the Loire Valley amidst the power struggles between the counts of Anjou and the counts of Blois. These structures typically comprised a mound surmounted by a keep, which was most often constructed from wood. It seems plausible that a similar system may have existed at Montbazon, situated on the site of the medieval keep. During the subsequent reconstruction of the fortress, stone was employed in place of wood. According to a charter by Robert II the Pious, written between 996 and 1006, the builder of the structure in question could have been Fulk Nerra, who constructed a castellum on land belonging to the Abbey of Saint-Paul de Cormery without prior authorization.
A second scenario is also a viable hypothesis that has gained support through recent research. The initial construction of the Montbazon castle site was a stone keep. The structure was 20 meters long by 15 meters wide and initially comprised two levels. It seems highly probable that this can be attributed to Fulk Nerra, before the stronghold's conquest by the House of Blois. The keep was promptly reinforced on its southern side with a substantial addition of earth, forming an "emplacement." Contrary to popular belief, the keep was not constructed on a mound; rather, the mound was subsequently incorporated to safeguard the base of the tower. Subsequently, between 1020 and 1110, possibly at the instigation of Geoffrey Martel, the son of Fulk Nerra, who had recaptured the fortress from the counts of Blois, this keep was partially destroyed at varying heights according to its sides, then rebuilt with two additional floors, while its base was repaired and an outwork was added to its western face.
12th and 13th centuries: Improvement of the defensive system and construction of a chapel
It is probable that during the reign of Henry II Plantagenet, between 1160 and 1180, a ditch was dug to the south of the site, and a curtain wall, apparently constructed with limestone extracted from the ditch, was erected between the ditch and the keep, whose lower floor was subsequently filled in. In this configuration, a walkway at the top of the curtain wall is a plausible hypothesis. A chapel was constructed in the 12th century to the north of the keep, but its foundations partially overlapped an older structure, perhaps from the early 11th century, which may have served a similar function. The fortress was subsequently captured by King Philip Augustus of France at the outset of the 13th century. During this same period, the curtain wall was rebuilt and reinforced at its southwestern corner with the addition of a three-story tower, which came to be known as the "Philip Augustus Tower" or the "Philippian Tower." Additionally, during the 13th century, an enclosure was constructed to the south of the curtain wall, thereby providing supplementary defense for this particularly exposed area. An archaeological survey conducted in 2015 revealed the existence of an enclosure north of the keep, which protected the entire promontory and was datable to the 13th century. This enclosure is likely connected to a tower at the northern tip of the site that collapsed in 2001. Therefore, the 13th century appears to have been a period of significant defensive improvements across the entire site.
15th to 18th century: Ephemeral new castle and fragile keep
In approximately 1425, Guy de La Rochefoucauld constructed a castle in opposition to the existing keep. The structure spanned approximately fifty meters in length and twenty meters in width, extending from east to west across the bailey and dividing it into two lower courtyards. No contemporary descriptions or representations clarify the architectural details of the structure. The only vague accounts, gathered orally by Amans-Alexis Monteil at the beginning of the 19th century, mention a "large building with wide mullioned windows." The castle served as a venue for hosting distinguished guests. On 3 November 1450, Antoinette de Maignelais married André de Villequier in the presence of Charles VII, who also spent the winter of 1458–1459 at the castle. Louis XI resided in Montbazon in 1472 and again in 1480. In 1560, Catherine de Medici and François II, accompanied by his wife Mary Stuart, were the guests of , lord of Montbazon. His son, , hosted the future Henry IV at the château-neuf in April 1589.
While the castle served as a residence for the lords and their distinguished guests, it also occasionally functioned as a prison. For instance, Cardinal Jean de la Balue, who was convicted of treason against the king, was detained at Montbazon for several months between his arrest on 23 May 1469, in Amboise and his transfer to Onzain in January or February 1470. He was held either in the keep or the château-neuf.
An enclosure was likely constructed in the 15th century, either contemporaneously with or shortly after the château-neuf, to safeguard the lower courtyards situated to the north of the fortress. It was linked to the urban wall and the Porte des Moulins to the east, both of which were erected contemporaneously. The structure included at least two defensive towers, one situated to the north and the other to the west. The latter is believed to correspond to the modern-day Lilian Tower. From the south to the east, it provided a ramp that served as access to the fortress after crossing a drawbridge. It was not until the modern era that a pathway for pedestrians was created to the west. However, the dating of this enclosure was called into question by archaeological diagnostics carried out in 2015, which suggested that it could be older, constructed shortly after the recently discovered 13th-century wall.