Juan Prim (hwän prēm), 1814–70, Spanish general and statesman. A Catalan officer, he fought for Isabella II against the Carlists and became one of the chief factional leaders in the fierce political rivalry of Isabella's reign, opposing at different times both Espartero and Gen. Ramón M. Narváez. He became (1847) governor-general of Puerto Rico, where he proved a stern administrator. As a commander (1859–60) in Morocco, he won the battle of Los Castillejos, for which he was made a grandee. He commanded the Spanish contingent in the international force sent against Mexico in 1861–62, but withdrew his troops when he realized that the French had ambitions to conquer Mexico. From 1863 to 1867, Prim made repeated attempts at military rebellion, and in 1868 he was finally successful, playing a large part in the overthrow of Isabella. As prime minister in the provisional government, he was a key figure in the choice of a new monarch. When the offer of the throne to a Hohenzollern prince fell through (indirectly bringing on the Franco-Prussian War), he secured the choice of Amadeus. However, before that prince could arrive in Spain, Prim was assassinated by his political enemies.