Webster retired from medicine in 1919 and returned to Shediac. There, he began work to record and popularize the history of New Brunswick. History had been a lifelong interest, and he was now able to devote his entire energies to the task. As a doctor, he had obtained the wealth and resources that enabled him to acquire important historical documents which had not yet been deposited in museums. Most of these documents would later be donated to the New Brunswick Museum, Saint John, but before then, he would use them to produce an important body of literature on the history of New Brunswick, Nova Scotia, and early Acadia (see list below). He was assisted by his wife in his work. For example, she translated various French language documents from the Acadian period, a difficult task given the archaic form of the language. A remarkable woman in her own right, Alice Webster was an important collector of art. She founded the Fine Arts Department of the New Brunswick Museum, created an endowment for the collection, and donated her own collection of regional and Asian art. She and Webster also acquired one of the most important artwork treasures in Canada, which portrays the death of James Wolfe in 1759, by James Barry and is on exhibition at the New Brunswick Museum.