Pope Leo XI (Italian: Leone XI; 2 June 1535 – 27 April 1605), born Alessandro Ottaviano de' Medici, was head of the Catholic Church and ruler of the Papal States from 1 April 1605 to his death, on 27 April 1605.[1] His pontificate is one of the briefest in history, having lasted under a month. He was from the prominent House of Medici originating from Florence.[2] Medici's mother opposed his entering the priesthood and sought to prevent it by having him given secular honours, but after her death he eventually was ordained a priest in 1567. In his career he served as Florence's ambassador to the pope, Bishop of Pistoia, Archbishop of Florence, Papal legate to France, and as the cardinal Prefect for the Congregation of Bishops and Regulars. He was elected to the papacy in the March 1605 papal conclave and served as pope for 27 days.
Alessandro felt the call to the priesthood, but his mother opposed this since he was the only male in the family. She sent him instead to the court of the Grand Duke of Tuscany, who appointed him a knight of San Stefano. In 1560 he travelled to Rome where he commenced a lifelong friendship and collaboration with Philip Neri, the future saint. It was Philip who predicted that Alessandro would ascend to the pontificate. His mother died in 1566, at which point he resumed his studies to become a priest. His ordination took place on 22 July 1567.[5]
In 1583 he was made a cardinal by Pope Sixtus V and on 9 January 1584 received the title of Cardinal-Priest of Santi Quirico e Giulitta, after a titular church previously known as San Ciriaco alle Terme Diocleziane. In later years, according to custom he would opt for other titular churches.[3][7]
On 14 March 1605, eleven days after the death of Clement VIII, 62 cardinals entered the conclave. Prominent among the candidates for the papacy were the great historianCaesar Baronius and the famous Jesuit controversialist Robert Bellarmine, future saint.
But Pietro Aldobrandini, the leader of the Italian party among the cardinals, allied with the French cardinals and brought about the election of Alessandro against the express wish of King Philip III of Spain. King Henry IV of France is said to have spent 300,000 écus in the promotion of Alessandro's candidacy.[9]
When he was elected, Leo XI was almost 70 years of age, and he died 27 days later.[10] His death came as a result of fatigue and cold in the ceremony of taking possession of the Basilica of St John Lateran on 17 April; he started suffering from a fever the following day.