Alice Mary Egan was born in Halifax, Nova Scotia, in 1872. Her parents were Lieutenant-Colonel Thomas J. Egan and Margaret Kelley. Her father owned a store that guns and sporting goods in downtown Halifax, and by the early 20th century was also offering taxidermy services. He was a prominent member of the Irish Catholic community of the city, a founding member of the Halifax Rifles militia unit and the author of the History of the Halifax Volunteer Battalion and Volunteer Companies 1859-1887. She had two sisters and one brother.

Around 1892 an Artist named Bessie Brown taught Alice Egan basic china painting techniques. Bessie Brown was the sister-in-law of John Thompson, prime minister of Canada. China painting was a popular medium at that time for professional women artists. It was one of the few respectable media for women artists, perhaps due to its associations with decorating the home. She went on to study china painting under Adelaïde Alsop Robineau in New York in 1896. Alice Egan leased a studio in Halifax in the commercial Roy Building. She equipped it with a kiln, purchased from the profits from her early sales, and used the studio to paint and to teach. Photographs show that she took care to give the room and feminine and domestic feeling despite its commercial purpose.

Alice Egan taught china painting at her studio in 1898–99. She was an instructor in china painting in the Victoria School of Art & Design in 1899-1900. She was particularly adept in lustre, an overglaze colorant fired at low temperatures. All the lustre seems brown when it is painted on the piece, but the colors emerge during firing. Sometimes Hagen would paint and fire several layer in succession. She used published pictures and designs for the images and motifs on her work, and sometimes drew from nature. The images were in a broad range of styles including naturalist, figurative, Asian and Art Nouveau.

In 1901 Alice married John Hagen of the Halifax and Bermuda Cable Company. They had two daughters, Rachel, born 1902, and Kathleen, born 1905. In 1910 John Hagen was transferred to Jamaica. Alice Hagen worked and taught in Jamaica, and her work was widely exhibited in the Caribbean islands. She sold her work and donated the proceeds to the Red Cross. She was the first woman to be awarded the bronze Musgrave Medal for her contribution to art in Jamaica, and the first woman to be awarded the silver medal. The Hagens returned to Halifax in 1916. Soon after she held an exhibition at the Women's Art Association Studio in Toronto. Alice Hagen continued to paint china, to teach and to exhibit in Halifax and Toronto. Her students were often school teachers and nuns.

In 1930 John Hagen retired from the Halifax and Bermuda Cable Company. The Hagens went on a tour of Europe, and Alice visited leading china manufacturers in England, France and Italy. In London she saw early Near Eastern lustre wares in a Persian Art Exhibit. In France she became interested in making pottery when she visited a pottery staffed by war veterans and saw how absorbed they were in their work. In retirement, John Hagen was very supportive of his wife, and would do the cooking to give her time for her work.

After returning in 1931 Alice studied pottery under Charles Prescott, who owned a small industrial pottery in Fairview, Nova Scotia. She obtained a kiln and made a studio in her home. When Alice Hagen began working in clay in 1931 the craft revival was already underway elsewhere, but in Nova Scotia she was a pioneer of studio pottery. In 1932 the Hagens moved to Mahone Bay, Nova Scotia. Alice Hagen launching into a new career as a potter. She exhibited her work and won various awards. She also taught a summer school for the Department of Education until around 1950.

A pioneer Artist potter, she experimented with local clays and glazes, and with clays from other parts of Canada. She developed a form of agateware using clays stained green, white and blue, which she called "Scotian Pebble". She continue to experiment until she was aged 93. According to Homer Lord, who worked with her for a month and a half in the summer of 1949, she was a very strong china Painter but not a strong potter. Her main interest in pottery was decoration of the surfaces, so she often cast rather than threw her pots. The Journalist Kay Hill visited Hagen in 1959 for an interview for the Atlantic Advocate. She said of the house,

John Hagen died in 1964. Alice Mary Hagen died in January 1972. The Nova Scotia government received forty-eight pieces of her handpainted china, glass and pottery, which are on display at the Citadel Museum in Halifax. In 1966 she gave the Mount Saint Vincent Academy many of her works of pottery and painted china. Her work is held by the Nova Scotia Museum, the Art Gallery of Nova Scotia, and Rideau Hall, Ottawa.