None is Too Many: Canada and the Jews of Europe 1933-1948 is a book co-authored by Canadian historians Irving Abella and Harold Troper.
First published in 1983 by Lester & Orpen Dennys, the book argues that, while many nations were complicit in the Holocaust for their refusal to admit Jewish people during the Nazi era, the Canadian government did less than other Western countries to help Jewish refugees between 1933 and 1948. According to official statistics, only 5,000 Jewish refugees entered Canada during this period, the lowest record of any Western country.
The authors point at Frederick Charles Blair, the head of immigration in the Mackenzie King administration for actively limiting Jewish immigration from the top. They also claim Blair had the full support of Mackenzie King, prime minister during the war, Canada's high commissioner to Britain Vincent Massey and both Anglophone and Francophone elites in general.
The title is based on an anecdote given in the book. In early 1945, an unidentified immigration agent was asked how many Jews would be allowed in Canada after the war. He replied "None is too many".