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Mary Calvert (Janssen)

Death: March 25, 1770
Chaillot (within the present 16th arrondissement of Paris), Region Ile-de-Paris, France
Immediate Family:

Daughter of Sir Theodore Janssen, MP, 1st Baronet Janssen of Wimbledon and Williamsa Janssen (Henley)
Wife of Charles Calvert, 5th Baron Baltimore and Alexander Bira de la Tour
Mother of Frederick Calvert, 6th Baron Baltimore; Louisa Browning (Calvert); Charles Calvert; Caroline Eden and Frances Dorothy Calvert (died young)
Sister of Sir Abraham Janssen, MP, 2nd Baronet; Barbara Bladen; Sir Henry Janssen, 3rd Baronet and Sir Stephen Theodore Janssen, MP, 4th Baronet

Managed by: Private User
Last Updated:

About Mary Calvert

From Darryl Lundy's Peerage page on

Mary Janssen[1]

  • F, #76410,
  • d. 25 March 1770
  • Last Edited=6 Jun 2008

Mary Janssen was the daughter of Sir Theodore Janssen, 1st Bt. and Williamsa Henley.[1]

She married Charles Calvert, 5th Baron Baltimore, son of Benedict Leonard Calvert, 4th Baron Baltimore and Lady Charlotte Lee, on 20 July 1730.[1]

She died on 25 March 1770 at Chaillot, Île-de-France, France.[1]

As a result of her marriage, Mary Janssen was styled as Baroness Baltimore on 20 July 1730. From 20 July 1730, her married name became Calvert.

Children of Mary Janssen and Charles Calvert, 5th Baron Baltimore

  • 1. Hon. Caroline Calvert+
  • 2. Hon. Louisa Calvert
  • 3. Frederick Calvert, 6th Baron Baltimore+1 b. 6 Feb 1731/32, d. 4 Sep 1771


1. [S6] G.E. Cokayne; with Vicary Gibbs, H.A. Doubleday, Geoffrey H. White, Duncan Warrand and Lord Howard de Walden, editors, The Complete Peerage of England, Scotland, Ireland, Great Britain and the United Kingdom, Extant, Extinct or Dormant, new ed., 13 volumes in 14 (1910-1959; reprint in 6 volumes, Gloucester, U.K.: Alan Sutton Publishing, 2000), volume I, page 395. Hereinafter cited as The Complete Peerage.

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Mary Calvert's Timeline

February 6, 1731
Epsom, Surrey, England, United Kingdom
January 21, 1738
England, United Kingdom
March 25, 1770
Chaillot (within the present 16th arrondissement of Paris), Region Ile-de-Paris, France