She began performing as a child actress at the Theatre Royal, Glasgow, in 1867, first speaking the following year in the juvenile role of Sybil in A Wolf in Sheep's Clothing.
In 1876, she became a member of Sarah Thorne's theatre company, playing the adult part of Emma Marigold in My Awful Dad, opposite Charles Mathews.
[3] In 1877, at the age of 15, she made her London début, creating the role of Maggie Macfarlane in W. S. Gilbert's comedy, Engaged, at the Haymarket Theatre with much success.
The Era reported: "A decidedly favourable impression was made by Miss Julia Stewart, who ... bewitched all present by her pretty face, her artless, winning style, her dainty treatment of the Scotch dialect, and the thorough freshness and naturalness of her acting throughout.
[9] She appeared with Dion Boucicault's company in 1887 in Boston as Cuba in Finn MacCool of Skibbereen[10] and in San Francisco in Drop Curtain Monographs.