Dillon was born in County Kilkenny, Ireland, on October 2, 1831, and came to the United States at age 17 in 1848.

[1] Making his way from New York City to Buffalo, and then to Chicago, he started doing factory work.

After a few years, Dillon went to New York and joined Laura Keene's company in 1862, and gained attention for his comedic skills.

[2] She was a sister of the wife of Jack Langrishe, who along with J.B. Atwater, ran the Milwaukee theatre where Dillon was playing at that time.

"[3] And a short newspaper blurb in 1892 reported Dillon was a member of the "Chicago Bi-Chloride of Gold Club" (which references a treatment for alcoholism popular in the 1890s), and "certainly should now be 'a model husband' if he never was before.