The National Gallery of Canada writes of O'Brien:
"O'Brien was born in a log cabin at Shanty Bay on the shores of Lake Simcoe in Upper Canada. Young Dick, as he was known in the family, exhibited an early interest in drawing and one he likely pursued as a student at Toronto's Upper Canada College. At age 15, he entered an architect's office and later practiced civil engineering, sketching during his holidays. He painted in watercolour and oil and from the 1850s showed considerable talent as a refined draughtsman and sensitive colourist. In 1873, he began to paint full-time. O'Brien painted landscapes in Ontario, Quebec, New Brunswick and, eventually, across the country to British Columbia.
O'Brien was elected vice-president of the Ontario Society of Artists (1874-1880). In 1879, O'Brien traveled to Ottawa to petition the newly appointed Governor General to accept the role of patron to the OSA. However, the Marquis of Lorne proposed a grander plan: to establish a national academy that would bring together the country's leading painters, sculptors and architects. O'Brien became the Royal Canadian Academy's first president. His dedication to both the OSA and the RCA ensured their legacy as vital cultural institutions.
On May 6, 1880, the Royal Canadian Academy held its first exhibition in Ottawa. O'Brien and each newly appointed Academician was required to donate a work of art exemplary of his or her talent. O'Brien submitted Sunrise on the Saguenay, Cape Trinity, as his diploma work. Painted in 1880, the poetic sunrise may have symbolized the promising beginnings of the development of the arts in Canada. These art works, including O'Brien's painting, formed the core collection of the newly established National Gallery of Canada. Kakabeka Falls, Kaministiquia River is the last oil painting he would exhibit for twelve years, changing his medium to watercolour. This work was borne from sketches of the Great Lakes region that O'Brien did as art editor for Picturesque Canada, an ambitious publishing project at the time. Nearing the end of the decade, O'Brien produced some large-scale watercolours such as A British Columbian Forest. On the newly completed Canadian Pacific Railway, in 1886, O'Brien was one of the first artists to travel west promoting the Rocky Mountains. In his journal and letters, O'Brien pronounced the British Columbia landscape to be something approaching heaven on earth. One of the most prominent watercolourists of his generation, O'Brien continued to paint in both oil and watercolour until 1899."
Lucius O'Brien died in Toronto on December 13, 1899.