 Next in line was Napoleon I's eldest brother Joseph Bonaparte (1768–1844), followed by Louis Bonaparte (1778–1846), but neither Joseph nor Louis had any interest in re-entering public life.When the Duke of Reichstadt died in 1832, Louis Napoleon became the "de facto" heir of the dynasty and the leader of the Bonapartist cause.In exile with his mother in Switzerland, he enrolled in the Swiss Army, trained to become an officer, and wrote a manual of artillery (his uncle Napoleon Bonaparte had become famous as an artillery officer).