Leopoldo O'Donnell y Jorís (Santa Cruz de Tenerife, January 12, 1809 - Biarritz, November 5, 1867).

He was a soldier and a Spanish politician.

He was the son of Charles O'Donnell (1772-1830). He participated in the first Carlist War, in the Elizabethan side and quickly was promoted to General in 1836. Thanks to his military successes, he was awarded the title of Count of Lucena. He also was promoted to Lieutenant Colonel (1839), was Chief of the General Staff of Baldomero Espartero (1793-1879), and as Captain General of Aragon and Valencia, expelled Ramón Cabrera (1806-1877) from the office of the Head Master. He conspired in favor of Maria Cristina during the Regency of Espartero. In 1841, he precipitated the general revolt against Espartero and facing the failure, he had to go into exile. He conspired with Ramón Narváez (1800-1868), in Paris, and the fall of Espartero, his old ally, distanced him from the country, naming him Captain General of Cuba. On his return, he participated in the conspiracies against Narvaez. During the Progressive Biennium, he was in the Ministry of war, from which taking advantage of the indecision of the moderates and the progressives division, he created a Centrist Liberal Party: the Liberal Union. With control of the army and the support of Isabel II on July 14, 1856, he took power but shortly after, when he did not accede to the demands of the Queen, he had to cede the post to Narváez.

In June 1858, he returned to power, until March 1863. During this period, the Liberal Union was characterized by political and economic stability and to let act with certain freedom to the opposition (constitutional reform, extension of voting, etc...). He also conducted numerous expeditions abroad (Cochinchina, Mexico, war in Africa, etc...) that contented the army. After that, he was awarded with the title of Duke of Tetuan. However, the Liberal Union disintegrated over time, causing the fall of O'Donnell, making way to a Moderate Government. Once again in the power in June 1865, after the events of the night of Saint Daniel, he began a policy of attraction of the progressives that safeguarded the Crown. But he failed in this attempt (pronouncements of the General Juan Prim (1814-1870) in Villarejo and the sergeants of San Gil). After that, Isabel II replaced him with Narváez (July 1866). O'Donnell retired to France, where he died shortly after.

He was in charge of the following Ministerial Departments:

- Minister of war: 30/07/1854 to 29/11/1854; 29/11/1854 to 12/10/1856; 21/06/10/07/1866 1865; 17/01/1863 at 02/03/1863.

- Minister of State. Interim during the absence of the holder: 27/07/1855 to 02/08/1855; 03/08/09/02/1862; 1862 20/10/1860 to 1861/02/06; 05/08/30/08/1860 1860; 04/08/1859 to 31/08/1859; 30/06/1858 to 02/07/1858; 09/04/1856 to 16/05/1856.

- President of the Cabinet: 1856/07/14 to 12/10/1856; 21/06/10/07/1866 1865; 17/01/1863 at 02/03/1863; 30/06/1858 to 17/01/1863.

- Temporary Minister of the Navy. Interim until the arrival of the holder: 14/07/1856 to 17/07/1856; 04/01/1866 to 24/01/1866; 25/11/1858 to 27/11/1858; 14/09/1859 to 05/10/1859; 13/07/1861 to 07/09/1861; 14/07/30/08/1862 1862; 17/01/1863 to 1863/02/09.

- Minister of War and Overseas: 30/06/1858 to 17/01/1863.

- Minister of Overseas: 17/01/1863 at 02/03/1863; 02/07/27/08/1865 1865.