|Bishop of Rome|
|Papacy began||1 April 1605|
|Papacy ended||27 April 1605|
|Ordination||22 July 1567|
by Antonio Altoviti
by Francisco Pacheco de Villena (Toledo)
|Created cardinal||12 December 1583|
by Pope Gregory XIII
|Birth name||Alessandro Ottaviano de' Medici|
|Born||2 June 1535|
Florence, Duchy of Florence
|Died||27 April 1605 (aged 69)|
Rome, Papal States
|Coat of arms|
|Other popes named Leo|
Pope Leo 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. 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. 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 the Bishops and Religious. He was elected to the papacy in the March 1605 papal conclave and served as pope for 27 days.
Alessandro Ottaviano de' Medici was born in Florence as the son of Francesca Salviati and Ottaviano. He was the great-nephew of Pope Leo X. Ottaviano died early in his son's life, and thereafter Alessandro was home schooled by a Dominican priest, Vincenzo Ercolano.
de' Medici felt the call to the priesthood, but his mother opposed his vocation 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, future saint. It was Neri who predicted that Alessandro would ascend to the pontificate. de' Medici's mother died in 1566 at which point he resumed his studies to become a priest. This led to his ordination on 22 July 1567.
Alessandro served as the Florentine ambassador to Pope Pius V from 1569 to 1584 and was later appointed by Pope Gregory XIII as the Bishop of Pistoia in 1573. In March 1573 after the appointment he received episcopal consecration in Rome. He was later made the Archbishop of Florence in 1574.
Medici was elevated into the cardinalate in 1583 and Pope Sixtus V made the Cardinal-Priest of Santi Quirico e Giulitta: a title he received on 9 January 1584. It was a titular church reverted from its previous name of San Ciriaco alle Terme Diocleziane. In the period after this, he would opt for other titular churches.
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 historian Cesare 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.
On 1 April 1605, Cardinal Alessandro de' Medici was elected as pope. He chose to be called Leo XI in honor of his uncle Pope Leo X. He was crowned on 10 April 1605 by the protodeacon, Cardinal Francesco Sforza and he took possession of the Basilica of Saint John Lateran on 17 April 1605.
When he was elected, Leo XI was almost 70 years of age, and he died 27 days later. 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.