[3][4] The family of Rohan claimed descent from the first kings of Brittany, and even from the legendary ruler Conan Meriadoc.

1028), was probably Viscount of Rennes as well and connected to the nobility of the Loire region, but he could have belonged to a Breton line holding estates around Josselin, where he built a castle.

Thus they became rivals of the Dukes of Brittany all through the Middle Ages, according to their interest, sometimes carrying out the most important charges of the Duchy faithfully, sometimes rebelling, as John II of Rohan did in the last years of Breton independence.

[9] To counter the power of the immense fiefs of the Rohan and Rieux families, which divided the Armorican peninsula into two equal parts, the Breton dukes denied them access to the coasts[10] and blocked them in the eastern part of the duchy through the fortresses of the Marches of Neustria#Breton March, whose main strongholds were Rennes and Nantes.

[11] The Rohans, then unpopular in a very Breton-tradition environment, were neutralized for the time being, and struck back only with the French army's direct support during the campaign of 1487 in the French–Breton War, which was marked by internal divisions among the barons of Brittany (Rohan, Rieux, Laval...) who constantly changed sides.

[12] In winter 1487–1488, John II was encircled by the ducal troops: his strongholds of La Chèze, Josselin, Rohan and Pontivy fell one after another in March 1488.

In 1491, the marriage between Anne of Brittany and Charles VIII initiated the annexation of the duchy to the French crown, a union that was permanently ratified in 1532.

The chief of the Protestant party during Marie de' Medici's regency Louis XIII's reign, he was one of the greatest captains of his time.

[14] The Rohans then applied themselves to giving credence to this version through historians such as Dom Morice, but also through favour, forcing and violating history if needed.

The Rohans had to force their claims through thanks to forged evidence (a common practice in these aristocratic families in the ancien régime).

This operation remained uncertain, the Dukes and peers of France being watchful, and the Rohans secured their position through other means: alliances with other families of princes étrangers exclusively (Lorraine, La Tour d'Auvergne and Condé), elevation of their estates into principalities, legally or not (Guéméné, Soubise, Lordship of Léon), accession to the Bishopric of Strasbourg, giving them the rank of Prince of the Empire, and the use of royal favor and their closeness to the kings (Louis XIV and Madame de Soubise, Louis XV and the Marshal of Soubise, Louis XVI and Madame de Marsan, governess of the Children of France).

The family of Rohan-Rochefort, which migrated to Austria in the early 19th century, is nowadays the last remaining branch of the House of Rohan.

It holds the genuine titles of Duke of Montbazon (1588, France), Duke of Bouillon (1816, Congress of Vienna), Prince of Rohan and Prince of the Holy Roman Empire with the style of Serene Highness (Durchlaucht), confirmed in 1808 by Emperor Francis II for all the members of the family.

For Hercule Mériadec de Rohan-Soubise (1669–1749), the estate of Frontenay-l'Abattu (département of Deux-Sèvres, Poitou) was erected in 1717 into a pairie-duché called the Duchy of Rohan-Rohan, to differentiate it from the title of Duke of Rohan held by the House of Rohan-Chabot.

Isabeau de Navarre (1512–1570) and was the father of René II, Viscount of Rohan and Lord of Léon († 1586) head of the Protestant party in France.

His only daughter Marguerite de Rohan (1617–1684) married in 1645 Henri Chabot (1615–1655) and gave birth to the Rohan-Chabot family.

Henri Chabot was created Duke of Rohan in 1648 by Louis XIV, and his descendants bear the name Rohan-Chabot.

Several members of the Rohan-Guéméné family migrated to Sychrov Castle in northern Bohemia, then part of the Austrian Empire, and were naturalized.