Robert Barr emigrated with his parents to Upper Canada at age four and was educated in Toronto at Toronto Normal School. Barr became a teacher and eventual headmaster of the Central School, Windsor, Ontario, from which position he began to contribute short stories - often based on first hand experiences - to the Detroit Free Press. In 1876 Barr quit his teaching position to become a staff member of that publication, in which his contributions appeared under the signature "Luke Sharp." His adoption of this nom de plume hearkened back to his days attending school in Toronto. At that time he would pass on his daily commute a shop sign reading, "Luke Sharpe, Undertaker", a combination of words Barr found amusing in their incongruity. At the Detroit Free Press Barr also rose through the ranks, eventually becoming news editor.

In 1881 Barr decided to "vamoose the ranch", as he put it, and removed to London, to establish there the weekly English edition of the Free Press. In 1892 he founded The Idler magazine, choosing Jerome K. Jerome as his collaborator (wanting, as Jerome said, "a popular name"). He retired from its co editorship in 1895. In London of the 1890s Barr became a more prolific author - turning out a book a year - and on familiar terms with many of the best-selling writers of his day, including Bret Harte and Stephen Crane. Most of his literary output was of the crime genre, then quite in vogue. When Arthur Conan Doyle's Sherlock Holmes stories were making their literary splash Barr published in the Idler the first Holmes parody, "The Adventures of Sherlaw Kombs" (1892), a spoof that was continued a decade later in another Barr story, "The Adventure of the Second Swag" (1904). Despite the jibe at the growing Holmes phenomenon Barr and Doyle remained on very good terms. Doyle describes him in his memoirs Memories and Adventures as, "a volcanic Anglo - or rather Scot-American, with a violent manner, a wealth of strong adjectives, and one of the kindest natures underneath it all."

• In a Steamer Chair and Other Stories (1892)[1]
• The Face and the Mask (1894)[2]
• In the Midst of Alarms (1894, 1900, 1912)[3]
• From Whose Bourne (1896)[4]
• One Day's Courtship (1896)[5]
• Revenge! [6]
• The Strong Arm [7]
• A Woman Intervenes (1896)[8]
• Tekla: A Romance of Love and War (1898)
• Jennie Baxter, Journalist (1899)[9]
• The Unchanging East (1900)
• The Victors (1901)
• A Prince of Good Fellows (1902)
• The O'Ruddy, A Romance, with Stephen Crane (1903)[10]
• The Tempestuous Petticoat (1905—12)
• A Rock in the Baltic (1906)[11]
• The Triumphs of Eugène Valmont (1906)[12]
• The Measure of the Rule (1907)
• Stranleigh's Millions (1909)
• The Sword Maker (1910)[13]
• The Palace of Logs (1912)

In the Midst of Alarms is a story of the attempted Fenian invasion of Canada in 1866. A Woman Intervenes is a story of love, finance, and American journalism. Countess Tekla essayed the historical novel.