Though he served in both the Massachusetts House of Representatives and the state Senate, he preferred to play a behind-the-scenes role as a party boss.

His parents were Irish Catholic immigrants who were both from New Ross, County Wexford and emigrated to America together to flee the Great Famine in Ireland.

Ten months after P. J. Kennedy's birth, his father Patrick also succumbed to the infectious epidemic that infested the family's East Boston neighborhood.

As the only surviving male, Kennedy was the first family member to receive a formal education, attending Sacred Heart, a private Catholic school in Boston.

[2] At the age of fourteen, young Kennedy left school to help support his mother and three older sisters, Mary, Joanna, and Margaret, as a stevedore on the Boston docks.

In the 1880s, with money he had saved from his modest earnings and help from his mother Bridget, he launched a business career by buying a saloon in the Haymarket Square neighborhood near downtown Boston.

Next, to capitalize on the social drinking of upper-class Bostonians, Kennedy purchased a third bar in an upscale East Boston hotel, the Maverick House.

"[5] A sociable man able to mix comfortably with both the Roman Catholic and the Protestant elite, Kennedy moved successfully into politics.

Beginning in 1884, he converted his popularity into service as a Democrat, a minority in the then Republican dominant power in the Massachusetts General Court.