Step 1: Understanding the Concept:
The question asks for the year of the revolution in Naples. This refers to the uprising in the Kingdom of the Two Sicilies (of which Naples was the capital) led by the Carbonari, a secret revolutionary society.
Step 2: Detailed Explanation:
The Naples Revolution took place in 1820-1821. It was part of a wave of revolutionary movements in Europe following the Napoleonic Wars. The Carbonari, an Italian secret society, led the uprising, forcing King Ferdinand I to promise a constitutional monarchy. However, the revolution was short-lived as it was suppressed by the Austrian army in March 1821, acting on behalf of the Holy Alliance to crush liberal movements. The year 1821 marks the culmination and suppression of this revolution.
Step 3: Final Answer:
The Naples Revolution happened in the period 1820-1821. Among the given options, 1821 is the correct choice.