Gaynor was born in
Oriskany, New York, on February 2, 1849, baptized as William James. His parents were Keiron K. Gaynor, an Irish-born farmer and blacksmith and Elizabeth (Handwright) Gaynor. He grew up on a farm with seven siblings. As a boy, he developed an interest in wandering the countryside where they lived, exploring nature and trying to figure out why things were the way they were. He was a studious boy, a trait which his father encouraged. As he was on the clumsy side, when it came to farmwork, his brother Tom usually took on the heavier chores. For his education, he first attended the local public school, then was sent to the Whiteboro
Seminary. The Gaynor family were
Irish and devout Catholics, thus, when weather permitted, on Sundays they would head to the nearby city of
Utica to attend
Mass at St. John's Church on Bleecker Street. As William entered his teenage years, he began to show a religious fervor that led his parents to think that he might have a
vocation to the Church. Both to test this, and for reasons of affordability, he was enrolled in the Assumption Academy in Utica. This was staffed by the
Brothers of the Christian Schools. William flourished in that school, and soon decided that he did indeed wish to become a member of their
religious congregation. In December 1863, he was sent to New York City to enter the
novitiate of the congregation. This was located at 44 East 2nd Street. The date of birth he gave at his admission was February 2, 1848, thus he was still fifteen at the time he was received. He was given the
habit of the institute, and named Brother Adrian Denys. He spent the next four years in this house, both in training and soon in teaching in nearby
parish schools. In 1868, he was one of a group of Brothers chosen to be sent to San Francisco to take care of
St. Mary's College there. They sailed from New York on July 16, aboard the . By this time, however, as well as the usual readings in history, philosophy and the
Church Fathers suggested to the Brothers, Gaynor had been reading and absorbing the reflection of a wide range of writers, mostly the ancient
Stoic philosophers. One lifetime favorite which he found was the
Autobiography of
Benjamin Franklin, where he found much that resonated with his own way of thinking. The book was to be his lifelong companion. As a result, however, by the time the small group of Brothers had arrived at their destination, Gaynor had lost his belief in organized
Christianity and had decided to leave the institute. Because of his youth, he had never taken
religious vows, as he was too young to do so under the regulations of the Brothers, thus there was no
canonical impediment to his departure. He made his way back home to Utica, where his family now lived, arriving late that same year. How he managed that journey he never shared, other than to say that it had not been an easy or pleasant experience. His father welcomed him back and helped him to secure a position with the law firm of Horatio and John Seymour, that he might read enough law to take the bar examination. This was to be the start of his entry into the political arena, as
Horatio Seymour had recently served as
Governor of New York, and had just run as the
Democratic Party's candidate for president against
Ulysses S. Grant. ==In politics==