Her genealogical sketch is here. Her family’s biography (from where this portrait was found): "Bertha Clara von Rothschild was one of the two daughters of Mayer Carl von Rothschild of Frankfurt to marry outside the Jewish faith. Bertha Clara - or Berthe - shared with her sisters a strong intellectual streak.
She married Alexandre Berthier, 3rd Prince de Wagram on 24 March 1882 in Paris. The couple had three children in four years. Her salons, which alternated between their properties on the avenue d'Alma and in the château de Grosbois, were enlivened by her charm and vivacity. Proust recalled her in A la recherche du temps perdu.
Berthe was an anglophile, and imbued her country parties at Grosbois with the spirit of England. She became involved with the history of the district and undertook an inventory of the library and archives of Grosbois, a testimony to her love of literature and her application to intellectual pursuits.
Berthe, who was born in Frankfurt on 2 January 1862, died on 18 September 1903.”
She also bore two daughters, shown in this portrait, Elisabeth Berthier de Wagram, (1885–1960) who married Prince Henri de La Tour d'Auvergne-Lauraguais (1876–1914) and Marguerite Berthier de Wagram, (5 Dec 1887 – 25 Jun 1966) who married Prince Jean Victor de Broglie (1878–1974).
