Gregg is born on June 17, 1867 in Shantonagh, County Westmeath, as the youngest child of Robert and Margaret Gregg, where they remain until 1872, when they move to Rockcorry, County Monaghan. He enters the village school in Rockcorry in 1872. On his second day of class, he is caught whispering to a schoolmate, which prompts the schoolmaster to hit the two children’s heads together. This incident profoundly damages his hearing for the rest of his life, rendering him unable to participate fully in school, unable to understand his teacher. This ultimately leads to him being unnecessarily perceived as dull or mentally challenged by his peers, teachers, and family.
In 1877, after seeing a friend use Pitman shorthand to take verbatim notes of a preacher’s sermon, Robert Gregg sees the shorthand skill as a powerful asset, so he makes it mandatory for his children to learn Pitman shorthand, with the exception of John, who is considered by his family too “simple” to learn it. None of the children succeed in fully learning the system. On his own, John learns the shorthand system of Samuel Taylor. He teaches himself the system fully, since he does not require the ability to hear in order to learn from the book.
Gregg says he initially set out to improve the English adaptation by John Matthew Sloan of the French Duployan shorthand, while working with one of Sloan’s sales agents, Thomas Malone. Malone publishes a system called Script Phonography, of which Gregg asserts a share in authorship is owed to him. Angered by Malone, he resigns from working with him and, encouraged by his older brother Samuel, publishes and copyrights his own system of shorthand in 1888. It is put forth in a brochure entitled Light-Line Phonography: The Phonetic Handwriting which he publishes in Liverpool, England.
In 1893, Gregg emigrates to the United States. That year he publishes Gregg shorthand with great success. He settles in Chicago in 1895 and by 1896 dozens of American public schools are teaching Gregg shorthand. The first Gregg Shorthand Association is formed in Chicago that year with 40 members. In 1897 the Gregg Publishing Company is formed to publish shorthand textbooks.
By 1907 Gregg is so successful that he opens an office in New York and then moves there. The popularity of his shorthand system continues to grow with it being taught in 533 school systems by 1912. In 1914 the New York City Board of Education approves the experimental introduction of Gregg shorthand into its high schools, where the Pitman system had long held sway. That same year the system is admitted to Columbia University (New York) and the University of California, Berkeley.
After World War I, Gregg travels extensively throughout Great Britain, hoping to popularize his system there. He is not quite as successful in this endeavor as he had been in America, but he sees Gregg shorthand become wildly popular in France, Germany, Poland, Spain, and especially Latin America, where for years Gregg’s birthday is a national holiday.
Following his wife’s death in 1928 Gregg returns to New York. He throws himself into volunteer work and continues to perfect the Gregg system. Over the next several years he is the recipient of several honorary degrees from American educational institutions. At one such ceremony in June 1930 he renews his acquaintance with Janet Kinley, daughter of the president of the University of Illinois. The two are married in October of that year. They purchase a home in Cannondale, a historic section of Wilton, Connecticut.
In the 1930s Gregg begins writing a history of shorthand, the subject that had been his lifelong obsession. The first chapter is printed in 1933 and successive chapters follow at intervals until 1936. He devotes time to charitable work and institutes scholarships in the arts and in court reporting at his Chicago school. His voluntary work on behalf of Allied soldiers and British civilians during World War II wins recognition from King George VI, who awards him a medal for “Service in the Cause of Freedom” in 1947.
In December 1947 Gregg undergoes surgery from which he seems to recover well. However, on February 23, 1948, he suffers a heart attack and dies in Cannondale, Connecticut at the age of eighty.