Princess Florestine Gabrielle Antoinette of Monaco (Full French name: Florestine Gabrielle Antoinette, Princesse de Monaco) (22 October 1833 in Fontenay-aux-Roses, Kingdom of the French – 4 April 1897 in Stuttgart, Kingdom of Württemberg) was the youngest child and only daughter of Florestan I, Prince of Monaco, and his wife Maria Caroline Gibert de Lametz. Florestine was a member of the House of Grimaldi and a Princess of Monaco by birth and a member of the House of Württemberg and Duchess consort of Urach and Countess of Württemberg through her marriage to Wilhelm, 1st Duke of Urach.

Florestine married Count Wilhelm of Württemberg (later Wilhelm, 1st Duke of Urach), son of Duke Wilhelm of Württemberg and his morganatic wife Baroness Wilhelmine von Tunderfeldt-Rhodis, on 15 February 1863 in Monaco. Florestine and Wilhelm had two sons:

Florestine's husband Wilhelm had converted to Roman Catholicism, in 1841, for his first marriage to Théodolinde de Beauharnais, who died in 1857.

Florestine, according to the rules governing succession to the throne of Monaco, was able to marry without relinquishing her rights. When her grandnephew Louis II, Prince of Monaco, ascended to the Monegasque throne, Florestine's son Wilhelm claimed his rights for his succession to the princely throne of Monaco and the Grimaldi noble titles. However, France had undergone two wars against Germany and did not wish to see German princes ruling the Principality of Monaco. Therefore, France reached an agreement with the principality allowing the illegitimate daughter of Louis II, Charlotte, to be his heir presumptive to the princely throne and Grimaldi noble titles. Charlotte renounced and ceded her rights to the princely throne on 30 May 1944 to her son Rainier who became Rainier III, Prince of Monaco.

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