The Death That Never Was
Correcting a 320-Year-Old Error in the Séguin dit Ladéroute Family
The Challenge
François Séguin dit Ladéroute holds a singular place in North American genealogy. Arriving in New France with the Carignan-Salières Regiment in 1665, he would become the progenitor of virtually all Séguin families across the continent. According to the Programme de recherche en démographie historique (PRDH), his descendants number between 1,890,000 and 2,310,000 Quebecers today—a staggering legacy spanning twelve generations.
For over three centuries, genealogical databases have recorded his death as 9 May 1704, with burial on 10 May 1704 at Notre-Dame-de-Montréal. This date appears in the PRDH-IGD database, Fichier Origine, and countless family trees. Yet a careful examination of notarial records reveals this date is impossible.
The question before us: When did François Séguin dit Ladéroute actually die? And how did such a significant error persist for over 320 years in one of New France's most important founding families?
What the Databases Say
The PRDH-IGD Individual record (#68331) for François Séguin Ladéroute states:
PRDH-IGD Individual record (#68331) for François Séguin Ladéroute, showing the erroneous death date of 09-May-1704 and burial 10-May-1704 at Notre-Dame-de-Montréal.
Death: 09-May-1704
Burial: 10-May-1704 Montréal (Notre-Dame-de-Montréal)
Fichier Origine, the authoritative database for immigrant origins, similarly records:
Fichier Origine record (#243774) for François Séguin dit Ladéroute, showing "Place and date of death: Montreal 09-05-1704"—the same erroneous date.
Place and date of death: Montreal 09-05-1704
However, a critical note now appears on Family Sheet [1732] in the Genealogy of the French in North America database, highlighted in yellow:
Family Sheet [1732] from the Genealogy of the French in North America database. Note also the descendant count: between 1,890,000 and 2,310,000 Quebecers across 12 generations. Source: Genealogy of the French in North America © 2005-2026 Denis Beauregard.
"Him: Error: other death date (DGFQ 1042), based on cm of his daughters (20-11-1700, not. Raimbault and 10-10-1701, not. Raimbault)"
This notation acknowledges the error based on the marriage contracts of his daughters. The PRDH-IGD database maintains a separate family record:
PRDH Family record (#4015) for François Séguin Ladéroute and Jeanne Petit, showing their 11 children. Note the marriage dates: Marie Madeleine married 1700-11-20 and Marie Jeanne married 1701-10-10—the two marriage contracts that prove François's death date.
Let us examine the primary sources directly to understand how this correction was determined.
The Evidence Trail
The key to establishing François's true death date lies in three documents from notary Pierre Raimbault and the parish registers of Longueuil—specifically, the marriage contracts and records of his daughters Marie Madeleine and Marie Jeanne.
Source: Notary Pierre Raimbault, Act No. 402, Montreal
Marriage contract of Louis Marie (Antoine Marie) and Marie Séguin, 20 November 1700. Notary Pierre Raimbault, Act No. 402. This document contains the critical phrase: "absnt pour son indisposition" (absent due to his illness)—proving François Séguin was still alive but seriously ill.
Key Finding: On 20 November 1700, François Séguin is described as:
- Still alive (Jeanne is his "wife," not "widow")
- Absent due to illness ("absnt pour son indisposition")
- Expected to ratify the contract when able
Notarial index page showing Act No. 402: "Mariage de Louis Marie + Marie Seguin" dated 20 9bre (November) 1700.
Ancestry database index confirming the marriage contract details: Louis Marie [Antoine Marie], Notarial Date 20 Nov 1700, Notary Pierre Rimbault, Act Number 402. Record accessed via FamilySearch link to Quebec, Canada, Notarial Records, 1637-1935.
Source: Notary Pierre Raimbault, Act No. 527, Montreal
Marriage contract of Joseph Robidou and Jeanne Séguin, 9 October 1701. Notary Pierre Raimbault, Act No. 527. This document contains the critical phrase identifying Jeanne Petit as "widow of the late François Séguin."
Critical Discovery: By 9 October 1701, Jeanne Petit is explicitly identified as:
- "veufue" — widow
- of "deffunct françois Seguin" — the late François Séguin
- described as "vivant habitant de Boucherville" — in his lifetime a resident of Boucherville
Source: Parish Register of Saint-Antoine-de-Longueuil (Francheville)
Marriage record of Joseph Robidou and Jeanne Séguin, 10 October 1701, Parish of Saint-Antoine-de-Longueuil (Francheville). The ceremony took place the day after the marriage contract was signed.
PRDH database index (#5267) for the marriage of Joseph Robidou and Jeanne Séguin, showing witness list including François Séguin (Father of bride) with ambiguous status markers.
PRDH Individual record (#65080) for Marie Jeanne Séguin Ladéroute, showing her marriage date of 10 October 1701 to Joseph Robidoux.
The PRDH index for this marriage (#5267) lists the witnesses:
| Rank | Name | Relationship |
|---|---|---|
| 05 | François SEGUIN | Father of bride (marked with dashes for status) |
| 06 | Jeanne PETIT | Mother of bride |
| 10 | Pierre SEGUIN | Brother of bride |
Note: While François Séguin appears in the PRDH index as "Father of 02," the marital status column shows dashes ("---") rather than the typical indicators. The previous day's marriage contract explicitly identified him as deceased. His listing here reflects his role as the bride's father rather than his presence at the ceremony.
The Breakthrough
The evidence is unambiguous. When we arrange these documents chronologically, the status of François Séguin at each date becomes clear:
Marriage Contract: Marie Madeleine Séguin & Louis Marie (Antoine Marie)
François is described as "absent due to his illness" (absnt pour son indisposition). Jeanne Petit is identified as his wife, indicating he is still alive but seriously ill.
STATUS: ALIVE (but ill)
Marriage Contract: Marie Jeanne Séguin & Joseph Robidou
Jeanne Petit is explicitly identified as "veufue de deffunct françois Seguin"—widow of the late François Séguin.
STATUS: DECEASED
Marriage Record: Marie Jeanne Séguin & Joseph Robidou
The church marriage takes place. François is not among the witnesses; his brother-in-law Charles Patenotre appears instead.
STATUS: DECEASED
Conclusion: François Séguin dit Ladéroute died sometime between 20 November 1700 (when he was alive but ill) and 9 October 1701 (when his wife is called his widow).
The illness noted in November 1700 was likely terminal. He did not live to see his daughter Marie Jeanne's marriage.
The Misidentified 1704 Burial
If François died between November 1700 and October 1701, what burial record was misidentified as his? The answer lies in the Notre-Dame-de-Montréal parish register for 10 May 1704:
Page from the Notre-Dame-de-Montréal parish register, 1700-1704, containing the burial record misidentified as François Séguin.
Detail of the 10 May 1704 burial record. Note the name clearly reads "Pierre Seguin dit La Deroute"—not François. This is the record that was erroneously attributed to François Séguin dit Ladéroute.
The record clearly states "Pierre Seguin dit La Deroute"—not François. This individual shared the dit name Ladéroute and came from Boucherville, leading to the misidentification. His exact relationship to the family remains uncertain, but he is definitively not François Séguin, who had been dead for nearly three years by May 1704.
Notably, François's son Pierre Séguin (baptized 24 August 1682) married Marie Barbe Filion on 4 February 1704 and lived until 9 November 1760, so the 1704 burial cannot be him either.
Summary of Evidence
| Date | Document | Key Phrase | François's Status |
|---|---|---|---|
| 20 Nov 1700 | Marriage Contract (Marie Madeleine/Louis Marie) |
"absnt pour son indisposition" (absent due to his illness) |
ALIVE (ill) |
| 9 Oct 1701 | Marriage Contract (Marie Jeanne/Joseph Robidou) |
"Jeanne Petit veufue de deffunct françois Seguin" (Jeanne Petit, widow of the late François Séguin) |
DECEASED |
| 10 Oct 1701 | Marriage Record (Marie Jeanne/Joseph Robidou) |
Father absent from witness list; Charles Patenotre (brother-in-law) present instead | DECEASED |
| 22 Feb 1702 | Marriage Record (François fils/Marie Louise Feuillon) |
Both parents listed; father's status ambiguous in index | DECEASED |
Corroborating Evidence: Son François's Marriage (February 1702)
Additional support comes from the marriage of François Séguin fils (the son) to Marie Louise Feuillon on 22 February 1702 in Boucherville:
Page from the Boucherville (Ste-Famille) parish register containing the marriage of François Séguin fils to Marie Louise Feuillon, 22 February 1702.
Ancestry.com database entry for the 1702 marriage of François Séguin (son), age 23, to Marie Louise Feuillon, showing parents François Séguin and Anne [Jeanne] Petit.
PRDH Marriage index (#3892) for François Séguin and Marie Louise Feuillon, 22 February 1702. Note that François Séguin Laderoutte (father) is listed as "Father of 01, Spouse of 04" but the marital status column shows ambiguous markers.
Database Corrections Required
| Database | Current Entry | Corrected Entry |
|---|---|---|
| PRDH-IGD (#68331) | Death: 09-May-1704 Burial: 10-May-1704 |
Death: Between 20 Nov 1700 and 9 Oct 1701 Burial: Unknown |
| Fichier Origine (#243774) | Place and date of death: Montreal 09-05-1704 | Death: Between 20 Nov 1700 and 9 Oct 1701 Place: Unknown (possibly Boucherville) |
Methodology Notes
Evidence Analysis Framework
This case study employs the Genealogical Proof Standard as defined by the Board for Certification of Genealogists:
- Reasonably exhaustive search: Marriage contracts and records for all children marrying near the death date were examined.
- Complete, accurate citations: All sources identified with repository, collection, and access information.
- Analysis and correlation: Evidence from multiple independent sources correlated to establish death window.
- Resolution of conflicts: The 1704 burial record conflict resolved by careful reading of the name ("Pierre" not "François").
- Soundly reasoned conclusion: Death date window established by terminus ante quem (widow designation) and terminus post quem (living but ill designation).
Source Citations (Evidence Explained Format)
Marriage Contract, Louis Marie & Marie Séguin (1700):
Quebec, Canada, Notarial Records, 1637-1935, database with images, FamilySearch (https://familysearch.org : accessed [date]), Pierre Raimbault (père), 1697-1727, Act 402, Marriage contract of Louis Marie and Marie Séguin, 20 November 1700; citing olm, cn1-340, Bibliothèque et Archives nationales du Québec.
Marriage Contract, Joseph Robidou & Jeanne Séguin (1701):
Quebec, Canada, Notarial Records, 1637-1935, database with images, FamilySearch (https://familysearch.org : accessed [date]), Pierre Raimbault (père), 1697-1727, Act 527, Marriage contract of Joseph Robidou and Jeanne Séguin, 9 October 1701; citing olm, cn1-340, Bibliothèque et Archives nationales du Québec.
Marriage Record, Joseph Robidou & Jeanne Séguin (1701):
Canada, Québec, registres paroissiaux catholiques, 1621-1979, database with images, FamilySearch (https://familysearch.org : accessed [date]), Longueuil, Saint-Antoine-de-Longueuil (Saint-Antoine-de-Padoue), Baptêmes, mariages, sépultures 1669-1730, image 93, Marriage of Joseph Robidou and Jeanne Séguin, 10 October 1701; citing Archives Nationales du Québec, Montreal.
Burial Record, Pierre Séguin dit La Déroute (1704):
Canada, Québec, registres paroissiaux catholiques, 1621-1979, database with images, FamilySearch (https://familysearch.org : accessed [date]), Montréal, Notre-Dame-de-Montréal, Baptêmes, mariages, sépultures 1700-1704, Burial of Pierre Séguin dit La Déroute, 10 May 1704; citing Archives Nationales du Québec, Montreal.
Implications for Descendants
This correction affects the genealogical records of between 1.89 and 2.31 million living descendants. While the error does not affect lineage—François Séguin dit Ladéroute remains the progenitor regardless of his death date—it does affect:
- Timeline accuracy in family histories and published genealogies
- Understanding of François's final years and the circumstances of his death
- Interpretation of his widow Jeanne Petit's lengthy widowhood (32 years until her death in 1733, not 29 years)
- Any research connecting the 1704 "Pierre Séguin dit La Déroute" burial to the family—that individual remains unidentified
The illness noted in November 1700 suggests François's death may have followed a period of decline rather than being sudden. His absence from his daughter's wedding contract and ceremony, less than a year later, indicates the illness was ultimately fatal.
Conclusion
François Séguin dit Ladéroute (baptized 4 July 1644, St-Aubin-en-Bray, Picardy, France) died between 20 November 1700 and 9 October 1701, likely in or near Boucherville, Quebec. He was approximately 56-57 years old.
The long-accepted death date of 9 May 1704 is erroneous, based on a misidentified burial record for "Pierre Séguin dit La Déroute"—a different individual whose relationship to the family remains undetermined.
This correction, supported by primary source analysis of notarial records, resolves a genealogical error that has persisted for over 320 years.
This case demonstrates the critical importance of examining original documents rather than relying solely on database indexes. The notation "absent due to his illness" in November 1700, combined with the designation "widow of the late François Séguin" in October 1701, provides irrefutable evidence that overturns centuries of accepted genealogical data.
For François's nearly two million descendants, this correction brings us closer to understanding the true story of their immigrant ancestor—a soldier who became a farmer, a husband, a father of eleven children, and the founder of one of New France's most prolific family lines.