Princess Frederica of Mecklenberg-Strelitz (3 March 1778-29 June 1841), Duchess of Cumberland and later Queen of Hanover, was the consort of Prince Ernest Augustus, 1st Duke of Cumberland (later King Ernst August I of Hanover), the fifth son and eighth child of King George III of the United Kingdom and Queen Charlotte.

Her Highness Princess Frederica Louisa Carolina Sophia Alexandra was born at Hanover, the fifth daughter of Duke Karl II of Mecklenberg-Strelitz (1741-1816) and his first wife, Frederica (1752-1782), the daughter of Georg Wilhelm, Landgrave of Hesse-Darmstadt. Her father assumed the title of Grand Duke of Meckelbenberg-Strelitz on 18 June 1815. Duchess Frederica was the niece of her future mother-in-law, Queen Charlotte (formerly Princess Charlotte of Mecklenburg-Strelitz).

Princess Frederica married firstly His Royal Highness Prince (Friedrich) Ludwig of Prussia (5 November 1773-23 December 1796), the younger son of King Friedrich Wilhelm II of Prussia, on 26 December 1793 at the Royal Palace, Berlin. The couple had three children:

• Prince Friedrich of Prussia (1794-1863); married Princess Louise of Anhalt-Bernbourg (1799-1882).
• Prince Karl of Prussia (1795-1798).
• Princess Frederike of Prussia (1796-1850); married Leopold IV, Duke of Anhalt-Dessau (1794-1871).

This marriage was dissolved in 1796. She then married His Serene Highness Prince Friedrich Wilhelm zu Solms-Braunfels (22 October 1770-13 April 1814) on 10 December 1798 at Berlin. The couple had five children:

• Princess Sophia zu Solms-Braunfels (b. and d. 1799).
• Prince Friedrich Wilhelm zu Solms-Braunfels (b. and d. 1800)
• Prince Wilhelm zu Solms-Braunfels (1801-1868); married Maria, Countess Kinsky von Wchinitz und Tettau (1802-1892).
• Princess Augusta zu Solms-Braunfels (1804-1865); married Albert, Prince (Prinz later Fürst) von Schwartzbourg-Roudolstadt (1798-1869).
• Prince Alexander zu Solms-Braunfels (1807-1867); married Louise, Princess (Fürstin) von Landsberg-Velen (1835-1894).
• Prince Karl zu Solms-Braunfels (1812-1875); married Sophie, Princess zu Löwenstein-Wertheim-Rosenberg (1814-1876).

Fourteen months after her second husband's death, she was married for a third time on 29 May 1815 at the parish church of Neu Strelitz, Germany, and again on 29 August 1815 at Carlton House, London to His Royal Highness Field Marshal Prince Ernest Augustus, Duke of Cumberland. The Duke and Duchess of Cumberland had three children:

• Princess Frederica of Cumberland (stillborn on 27 January 1817).
• An unnamed stillborn daughter (April 1818).
• Prince George of Cumberland (later King George V of Hanover) (27 May 1819-12 June 1878).

The Duchess of Cumberland became Queen of Hanover upon the ascension of her third husband to the Hanoverian throne on 20 June 1837. Queen Frederica of Hanover died in 1841 at Hanover and was buried in the Chapel at Schloss Herrenhausen.