Mary Dawson, Countess of Dartrey

Mary Frances Dawson, Countess of Dartrey, 25th Baroness de Ros of Helmsley (née FitzGerald-de Ros) (31 July 1854 – 4 May 1939) was a British peer. She was born in London. Her parents were Dudley FitzGerald-de Ros and Lady Elizabeth Egerton. Upon her father's death in 1907, Mary succeeded to the title.

The 25th Baroness married Anthony Dawson, 3rd Earl of Dartrey (1855–1933) in London on 2 October 1878. To them were born three daughters; the Barony of de Ros descended among their issue:

• Lady Una Mary Dawson (born 1879), who became the 26th Baroness upon the termination of the abeyance in 1943.
• Lady Maude Elizabeth Dawson (born 1882)
• Lady Eleanor Charlotte Augusta Dawson (born 1885)

References

• "de Ros, Baron (Maxwell) (Baron E 1264)." Debrett's Peerage & Baronetage 1995. London: Debrett's Peerage Limited, 1995. pp. 362–363.
• Ducal House of Leinster