Princess Gertrude of Hanau and Hořowitz (née Falkenstein; 18 May 1803 – 9 July 1882), was a German aristocrat.

[1] Elector William II made her Countess of Schaumburg (with the style of Illustrious Highness), upon her Catholic conversion to the Reformed faith and her marriage on 26 June 1831 with Frederick William, and her then-husband (last Prince-Elector from 1847 to 1866) made her Princess (Fürstin) of Hanau and to Hořowitz in 1853 (with the style of Serene Highness in 1862).

Gertrud and Frederick William had nine children, some born before marriage, who were also made count/esse/s (Grafen) of Schaumburg with the style of Illustrious Highness, then prince/sse/s (Prinzen) of Hanau in 1853 and granted the style of Serene Highness in 1862:[2] Gertrud von Hanau was given several titles, which her children could inherit, but her irregular status[3] barred her children from inheriting full entitlement and recognition of their princely rights by the brotherly Grand Duchy of Hesse (still-reigning and not annexed like the Electorate of Hesse following the Austro-Prussian War).

In 1867, Gertrude von Hanau, her husband and their six sons left the former Electorate of Hesse-Cassel and went in exile at Hořowitz Castle, in Bohemia where the princely title of Hanau was recognized by the Austrian imperial authorities since March 1855.

The deposed Elector Frederick William died on 6 January 1875 and bequeathed his immense fortune to her, his widow, and to their children.