Isabella II (1830-1904) was queen of Spain from 1833 to 1868. She was Spain's first true constitutional monarch during a period of growing social and political conflicts.

Born in Madrid on Oct. 10, 1830, Isabella was the daughter of Ferdinand VII of Spain and Maria Cristina of Naples. Her uncle Don Carlos refused to recognize her right to the throne, and after the death of Ferdinand in late 1833 a bitter civil war broke out between the conservative elements, who supported Don Carlos, and the liberal groups, who supported the young princess and her mother, the Queen Regent. The Carlists were defeated in 1839, but the following year Baldomero Espartero, a liberal and the most powerful general in the country, forced Maria Cristina to leave Spain. Isabella remained behind.

Three years later, the conservatives overthrew Espartero and his liberal supporters and on Nov. 8, 1843, had 13-year-old Isabella declared legally of age and crowned queen. Isabella's...