Mary Janssen

(died 1770)
Person human Q75343909
Press Enter · cited answer in seconds

Summary

Mary Janssen was born on 1715[1]. She died on March 25, 1770[2].

Key Facts

  • Father: Sir Theodore Janssen, 1st Baronet[3]
  • Mother: Williamsa Henley[4]
  • Spouse: Charles Calvert, 5th Baron Baltimore[5]
  • Child: Caroline Eden[6], Louisa Calvert[7], Frederick Calvert, 6th Baron Baltimore[8]
  • Sex or gender: female[9]
  • Family name: Janssen[10]
  • Given name: Mary[11]
  • Sibling: Abraham Janssen[12], Stephen Theodore Janssen[13], William Janssen[14], Sir Henry Janssen, 3rd Bt.[15], Barbara Janssen[16], Q141691846[17]
  • P14921: mary-janssen[18]

FAQs

Who were Mary Janssen's parents?

Mary Janssen's father was Sir Theodore Janssen, 1st Baronet[3]. Mary Janssen's mother was Williamsa Henley[4].

Who was Mary Janssen married to?

Mary Janssen's spouses include Charles Calvert, 5th Baron Baltimore[5].

References

Programmatic citations — every numbered marker resolves to a verifiable graph row below.

Direct Wikidata claims

  1. [9] ↑ . The Peerage. wikidata.org.
  2. [3] ↑ . The Peerage. wikidata.org.
  3. [4] ↑ . The Peerage. wikidata.org.
  4. [5] ↑ . Q75653886. Retrieved . wikidata.org.
  5. [6] ↑ . The Peerage. wikidata.org.
  6. [7] ↑ . The Peerage. wikidata.org.
  7. [8] ↑ . The Peerage. wikidata.org.
  8. [1] ↑ . WikiTree. wikidata.org.
  9. [2] ↑ . The Peerage. wikidata.org.
  10. [10] ↑ . wikidata.org.
  11. [11] ↑ . wikidata.org.
  12. [12] ↑ . wikidata.org.
  13. [13] ↑ . wikidata.org.
  14. [14] ↑ . wikidata.org.
  15. [15] ↑ . wikidata.org.
  16. [16] ↑ . wikidata.org.
  17. [17] ↑ . wikidata.org.
  18. [18] ↑ . wikidata.org.

📑 Cite this page

Use these citations when quoting this entity in research, articles, AI prompts, or wherever provenance matters. We aggregate Wikidata + Wikipedia + authoritative open-data sources; the stitched, scored, cross-referenced view is what 4ort.xyz contributes.

APA 4ort.xyz Knowledge Graph. (2026). Mary Janssen. Retrieved October 10, 2026, from https://4ort.xyz/entity/mary-janssen
MLA “Mary Janssen.” 4ort.xyz Knowledge Graph, 4ort.xyz, 10 Oct. 2026, https://4ort.xyz/entity/mary-janssen.
BibTeX @misc{4ortxyz_mary-janssen_2026, author = {{4ort.xyz Knowledge Graph}}, title = {{Mary Janssen}}, year = {2026}, url = {https://4ort.xyz/entity/mary-janssen}, note = {Accessed: 2026-10-10}}
LLM prompt According to 4ort.xyz Knowledge Graph (aggregator of Wikidata, Wikipedia, and authoritative open-data sources): Mary Janssen — https://4ort.xyz/entity/mary-janssen (retrieved 2026-10-10)

Canonical URL: https://4ort.xyz/entity/mary-janssen · Last refreshed:

Edit History

Rolling log of changes to this entity's Wikidata record. Values shown reflect the current state of each edited property — follow the history link to see the precise diff for any edit.

  1. 7d ago · Pigsonthewing · 2026-10-10 view diff on Wikidata ↗
    Sibling → Abraham Janssen, Stephen Theodore Janssen, William Janssen +3
    Claims rich → —
    "/* wbeditentity-statements-single-property-add:1||6 */ Sibling, Adding statement(s) using [[:toollabs:wikidata-todo/relator2|Relator2]]"
  2. 9d ago · Magnus Manske · 2026-10-08 view diff on Wikidata ↗
    Imported from → —
    Given name → Mary
    Father → Sir Theodore Janssen, 1st Baronet
    Family name → Janssen
    + 15 other properties edited (see Wikidata diff for full list)
    "/* wbcreateclaim-create:1| */ P14921: mary-janssen, [[:toollabs:quickstatements/#/batch/289878|batch #289878]]"
Live feed via Wikidata EventStreams. New edits appear within minutes of being made on Wikidata.