John Melchior Bosco was born on 16th August 1815 in a little hamlet called "the Becchi" in the Parish of Castelnuovo d'Asti, twenty miles from Turin, Northern Italy. He was the youngest of a family that consisted of his mother and father, his brother Joseph, stepbrother Anthony and his grandmother. They were poor farmers and lived a very hard, frugal life.

When John was two years old, his father died, and it was left to his mother, Margaret, to bring the family up as best she could. She instilled in John a profound love and respect for God and taught him to be honest and hard-working. At the age of nine, John had a special dream that was to guide his future. In this dream, a man of noble appearance and a majestic lady seemed to be telling John of the qualities he would need to work with young people. As he watched wild animals become lambs, he was told to prepare himself to transform young people the same way. This dream was to recur a number of times throughout John's life almost as a reminder of what he was called to do.

John's early education was patchy, but he showed he was smart with a great memory. He was also agile and acrobatic. At ten years old he was already a natural leader, and gathered groups of young people to watch his acrobatic show, then listen as he repeated parts of the Sunday sermon. However, because of Anthony's opposition, he made little progress in his education. Anthony resented John going to school, and hated to see books lying around the house. When Anthony began to be physically violent towards John, his mother decided he had to leave home. She sent him to stay with cousins of hers, the Moglias, who had a farm near Moncucco. John had a happy time with the Moglias, and although his education had stalled somewhat, he found plenty of time to develop his relationship with God, as he worked in the fields.

In November of 1829, Margaret brought John home to the Becchi. Anthony was less resentful and thinking of getting married. A few days later, John met an old priest called Don Calosso as both were making their way home from a parish mission in a nearby Church. Don Calosso was the priest at Murialdo and was impressed by John's memory and understanding of the sermons he had heard at the mission. He offered to tutor John in Latin every day and John spent as much time as he could with the gentle old man. In Don Calosso John found a father figure and a spiritual guide, who promised to see him all the way to the priesthood. Unfortunately, a year after their meeting, Don Calosso died suddenly after a stroke. John was devastated. Although Don Calosso left him enough money for his education, John felt obliged to hand it over to the old priest's relatives. Another avenue of learning was now closed.

Finally, in 1831, when John was sixteen, his mother sent him to school in Chieri, where his intelligence soon enabled him to catch up with his lessons. While in Chieri, he lodged with various people from whom he learned a number of trades that he would later teach his boys. At the end of his secondary schooling, he nearly joined the Franciscans, but after advice from friends, he entered the Diocesan Seminary.

Between 1835 and 1841, John studied Philosophy and Theology in preparation for becoming a priest.

On 5th June 1841, in the presence of his proud mother, John was ordained a priest by Archbishop Fransoni and became Don Bosco. His youthful ambition to be a priest had been achieved.