Aloysius was born into the noble family of Castiglione in 1568, and was raised according to the norms of courtly etiquette. When he was four years old, his father began training him in the warrior arts, including the wearing of a suit of armor. At nine years old, the boy was sent to the Medici court, known as "the most corrupt court in Italy."
Aloysius began to "come into his own" as it were, when he was barely twelve years old. He began reading the lives of the saints, praying the psalms, and reading Peter Canisius' (SJ) book on Christian Doctrine. His reading was "brought to life" when Charles Borromeo visited the Gonzaga family, and prepared Aloysius for his First Communion on July 22, 1580. Aloysius' graced awareness of the power of this Sacrament was evident in his religious practices: daily Mass attendance, weekly reception of Communion, and fasting three times each week.
As he entered his teen-age years, Aloysius was made a page in the court of Empress Maria Theresa, and a knight of Saint James. But he countered these "honors" with weekly reception of the Sacrament of Penance and regular conversations with local Jesuit priests. When he expressed his desire to enter the Society of Jesus, his father refused and sent Aloysius with his brother on a tour of European courts.
It was only in 1585, that Aloysius finally gained his father's permission to enter the Society of Jesus, thereby turning his back on all that his family and society valued. He was admitted to the novitiate in Rome on November 25, 1585. His maxim at that time was: "I am a twisted piece of iron; I entered religious life to be untwisted straight."
In November 1587, Aloysius pronounced his vows, and early the following year he received minor orders and began theology studies. As a student, he was described as having "a penetrating intellect" and "a memory like a steel trap." As a community member, he was known for his kindness and gentle courtesy. His superiors noted his devotion to the Passion of Christ and the Eucharist, and his "unwearying" care for his neighbors.
Early in the decade of the 1590's famine and plague broke out in Rome. Aloysius begged food for the suffering, washed and fed them, and prepared them for the sacraments. He taught the catechism to ragamuffins, and occasionally and with permission of his superiors, visited prisons and hospitals. He told his spiritual director, [the future saint] Robert Bellarmine that he felt "an extraordinary desire to work and serve God."
On March 3, 1591 Aloysius himself was stricken with the plague and died on the feast of Corpus Christi, June 21, 1591. He was buried in the church of the Jesuits' Roman College and later moved to their Church of the Gesu.
Aloysius Gonzaga was beatified in 1605, and canonized, along with St. Stanislaus Kostka, on December 31, 1726. Aloysius was made patron of youth on December 31, 1726.