Alessandro Napoleoni was born on Sardinia, Italy in 1786. He joined the Italian army only sixteen years old, and soon rose through the ranks. As a captain, he participated in the Italian conquest of Cuba. In 1810, then a major, he was promoted colonel by king Gioacchino of Italy personally. More important however was the fact that the old king who liked the young officer decided to make Alessandro his successor, just like the adoptive emperors of Rome, since he was the last one living of his family and feared that his kingdom might break together.