Auxonne (French pronunciation: [oksɔn] or [osɔn]) is a commune in the Côte-d'Or department in the Bourgogne-Franche-Comté region of eastern France.

The current spelling of the name comes from a habit of copyists of the Middle Ages who replaced the double "s" by a cross which does not change the pronunciation.

The city of Auxonne is specifically in the alluvial ribbon called the Val de Saône – a band a few kilometres wide that follows the river.

Its immediate limit in the Auxonne area is ten kilometres to the east where there is a rise of the Massif de la Serre to an altitude of about 400 metres.

Modern historians agree on doubting the veracity of the assertions contained in the Chronicle of Saint-Pierre de Bèze (the name of the monastery founded by Amalgaire who is referred to as Amauger in the History of Burgundy[11]) in the first half of the 7th century concerning the term Assona to refer to Auxonne in the first half of the 7th century.

Count Manassès built them a new monastery (circa 895–896) in Frankish Burgundy in the County of Beaune on the slopes of Mount Vergy.

In 1172 the city had grown in importance: Count Stephen I of Auxonne, the younger branch of Burgundy County and son of William (died 1157), had settled there.

On 15 June that year, under an exchange agreement concluded at Saint-Jean-de-Losne between John, Count of Chalon (1190-30 September 1267) (the main character of the agreement and son of Stephen III, long associated with his father's business and heir of Beatrice de Chalon (1170-7 April 1227) his mother and Stephen III himself) and Hugh IV, Duke of Burgundy, the town of Auxonne and all the possessions of Stephen III in the basin of the Saône were transferred to the Duke of Burgundy in exchange for the Barony of Salins and ten strategic positions of the first importance in the County.

In coming under the rule of the Dukes of Burgundy, Auxonne became a bridgehead of the duchy on the eastern bank of the Saône, on Holy Roman Empire soil, and escaped the Germanic influence.

The special status of Outer Saône lands, which were not a domain of the crown given prerogatives, did not stop Louis XI from his conquest.

Auxonne held out for 12 days in the siege by the royal army commanded by Charles d'Amboise before opening its doors on 4 June 1477 to the French invader.

For political ends Louis XI, while he solemnly confirmed the maintenance of all the privileges of the town to ensure the loyalty of his new subjects, hastened to build a mighty fortress, the Chateau d'Auxonne, at Auxonne at the province's expense, which still dominates Iliote square, to guard against any attempt of rebellion.

Charles VIII challenged Louis XI as, while he was engaged to Marguerite, daughter of Mary of Burgundy and Maximilian I of Habsburg, heiress of the Duchy of Burgundy, and after the dowry of his future wife arrived in the County, he preferred to marry Anne, heiress of Brittany, and thus took the important Duchy of Brittany from the kingdom of France.

On 14 January 1526 the Treaty of Madrid was signed, after the Battle of Pavia, between François I and Charles V. The King of France was forced to abandon Burgundy and the County of Auxonne, among other territories.

In front of the walls of the city Lannoy, commander of the imperial armies, found such strong resistance on the part of all the people he had to give up.

Jean de Saulx-Tavannes, governor of the city and the Chateau of Auxonne at first took the measures imposed then secretly strengthened the garrison of the castle as he suspected that the inhabitants of conspiring with Mayenne to deliver it to him instead.

The Count of Charny, a close relative of Jean de Saulx,[12] Lieutenant General in Burgundy, approved this act of loyalty to the Crown by the people of Auxonne.

When the King was informed he praised the people for their loyalty but concessions to Leaguers which were formalised by the signing of the Treaty of Nemours on 7 July 1585 forced Henry III to equivocate.

He asked the people to deliver Tavannes into the hands of Charny and named Claude de Bauffremont, Baron of Sennecey known for his Mayenne sympathies, as governor of the town and Chateau of Auxonne.

In complete defiance and sniffing betrayal, the people of Auxonne handed Tavannes to the County of Charny who shut him up in his castle at Pagny, refused Sennecey as governor, and continued to claim in his place the Baron of Pluvault.

His patience tired, Henry III, by letters patent of 1 May 1586, declared the Auxonne people guilty of Lèse-majesté and ordered action by force so arrangements were made accordingly.

Jean Delacroix (or John of the Cross), a countryman of Auxonnais and private secretary to Catherine de' Medici[13] arrived with his deputation to the king with Letters of credence for Sir Charny giving him full powers to deal with the people .

The Treaty revoked letters that declared the people of Auxonne guilty of lese majeste, exempted them from contribution for nine years, and granted a gratuity of 90,000 francs to the Baron of Pluvault.

This treaty was approved by letters patent of 19 August 1586 and on the 25th of the same month the Baron of Sennecey was received and installed as governor of the town and Chateau of Auxonne.

There is also a small museum in a tower of the Chateau of Auxonne, his set square, his fencing foil, and objects he offered during his stay, as well as one of his hats.

In 1516, under the direction of Master Loys – the architect of the church of Saint-Michel de Dijon – the construction of the portal surmounted by two towers of unequal heights began.

This campaign included two side portals, implementation of a slender, octagonal, pyramidal, and slightly twisted tower called a Crooked spire.