Short answers, pulled from the story.
The Italian Republic was a French client state in northern Italy that existed from 1802 to 1805. Napoleon Bonaparte served as its president and Milan was its capital. It was the successor to the Cisalpine Republic and was transformed into the Kingdom of Italy in 1805.
Francesco Melzi d'Eril was the vice-president of the Italian Republic and effectively governed its domestic affairs during the three years of the republic's existence. He introduced obligatory conscription to Italy and, despite never submitting to Napoleon's authority, earned Napoleon's deep private respect throughout the years of the French empire.
The Italian Republic covered more than 42,500 square kilometres and had a population of 3,840,000 people spread across twelve departments, primarily in Lombardy and Romagna. Milan, the capital, had around 124,000 inhabitants as of 1764.
The Italian Republic signed a treaty of friendship and commerce with the Republic of San Marino on the 10th of June 1802 and a Concordat with the Holy See on the 16th of September 1803.
The Italian Republic's constitution placed sovereignty in three electoral colleges based in Milan, Bologna, and Brescia, which elected a twenty-one-member supervisory body called the Censorship. Napoleon as president held full executive powers, while the Legislative Body of 75 members could only approve or reject laws, with debate reserved for a fifteen-member Chamber of Orators.
The Italian Republic ended in 1805 when Napoleon assumed the title of Emperor of the French. It was transformed into the Kingdom of Italy, with Napoleon as king and his stepson Eugène de Beauharnais as viceroy.