Genealogy in Essonne (91): guide for your archive research

Genealogy checklist - Browse archives and online resources to search for your ancestors in Essonne.

Genealogy in Essonne (91): guide for your archive research

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updated: January 7, 2026


Essonne is a recent department but built on very ancient lands, nestled between Beauce, Hurepoix, Brie, and Gâtinais, which have long lived in the direct orbit of Paris. For a genealogist, this is a territory where ancestors can appear both in present-day Essonne, in old Seine-et-Oise, or in the capital, with significant population movements starting in the 1960s.


Officially created on January 1, 1968, Essonne is the result of dividing the old Seine-et-Oise into three departments (Essonne, Yvelines, Val-d'Oise) as decided by the law of July 10, 1964 to accompany the demographic explosion of the Paris region. This territory gathers parts of Hurepoix, Brie, Gâtinais, and the northern Beauce, long structured by towns like Étampes, Dourdan, Corbeil, Montlhéry, or Arpajon, already active during the Gallo-Roman period and the Middle Ages. It is bordered by the departments of Yvelines, of Hauts-de-Seine, of Val-de-Marne, of Seine-et-Marne, of Loiret and of Eure-et-Loir.

Starting in the 19th century, the arrival of the railway (Corbeil-Paris line in 1840, then Paris-Orléans) and the development of industries along the Seine gradually transformed these countryside areas into the industrial-urban suburbs of the capital, a prelude to the future new towns and large housing projects of the second half of the 20th century.



📂 The archives of Essonne


Essonne Departmental Archives: find your ancestors


Visit the Essonne Departmental Archives:

📍 38 rue Commandant Maurice Arnoux, 91730 Chamarande


Contact the Essonne Departmental Archives:

📞 01 69 27 14 14

📧 Send a message


Consult the online archives on the Essonne Departmental Archives website:



Online records


Unusual records



Migrations in Essonne


  • Before 1800 : before the creation of departments, the lands corresponding to present-day Essonne were part of Île-de-France and were strongly marked by proximity to Paris, with continuous occupation since prehistory (Magdalénien site of Étiolles, Gallo-Roman villas of Orsay, oppidum of Arpajon). Mobilities were mainly local: peasants, artisans, merchants, and men of the Church moved between fortified towns (Étampes, Corbeil, Dourdan, Montlhéry) and surrounding countryside, often within a radius of a few dozen kilometers.

    The wars (Hundred Years' War, conflicts of the 14th–17th centuries, Fronde) caused temporary displacements, with populations taking refuge behind urban walls when the countryside was ravaged. For genealogists, this is reflected in ancestors frequently changing parishes within a restricted area, with scattered records among neighboring villages depending on the same lordships or bailiwicks.


  • 19th Century: in the 19th century, the territory of future Essonne remained officially part of Seine-et-Oise, but the arrival of the railway from 1840 profoundly changed mobilities: the Corbeil–Paris and Paris–Orléans lines facilitated exchanges and the establishment of factories along the Seine. Industries (milling, gunpowder, various manufactories) multiplied, particularly around Corbeil-Essonnes, while the surrounding countryside continued to produce cereals and beets, in a context of generalized rural exodus to Paris.

    Many young people then left the villages to become workers or servants in the capital or in the industrial towns of the area, leading to typical routes in the records: 'Seine-et-Oise village → Paris → return or settlement in a suburb'. For your research, this period requires consulting both the archives of former Seine-et-Oise and Paris civil records, as the same individual could be born in an Essonne village, married in Paris, and died in a suburb later attached to Essonne.


  • 1900–1968 : at the beginning of the 20th century, the area saw increasing development of industrial and residential functions linked to the Paris region, with the expansion of rail and road networks and the multiplication of industrial establishments (gunpowder mill in Essonnes, factories in Corbeil, etc.).

    World War I and then World War II affected the region, but it was mainly the Thirty Glorious Years that transformed the landscape: demographic explosion of Seine-et-Oise, creation of new neighborhoods and large housing developments, new town projects.

    The 1964 law, applied on January 1, 1968, divided Seine-et-Oise and created Essonne to better manage this demographic and urban boom, with Évry as the new town and future prefecture. In the 1970s, the installation of major facilities (prefecture, courthouse, Évry-Courcouronnes train station, École Polytechnique in Palaiseau) attracted new residents from central Paris, other Île-de-France departments, and the provinces.


For more information:

Île-de-France – History and Memory of Immigration since 1789

L'Essonne and its History

The Essonne Department

History of the Essonne Department



📷 Essonne in images


The videos


The images and old postcards


The old maps of the department

  • From Cassini's villages to today's communes: the department of Essonne
  • On Old Maps Online: the old maps of the department
  • On Gallica: the old maps of Essonne


📖 The history of Essonne



On Gallica: the books, the press and the manuscripts to learn everything about the Essonne department



🖋️ Genealogy sites in Essonne


Genealogy circles and associations in Essonne or nearby



Happy researching! 


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