Background: In the 1920s, eight of nine Canadian provinces legalized alcohol sales, ending prohibition in favor of government control. Much has been written about the rise and fall of Prohibition in North America, but there is little work examining these events in the light of current drug policy debates. This paper attempts to fill some of these gaps. Methods: The aims of this paper are primarily exploratory and descriptive. Following a literature review, it draws from secondary and some primary sources to explore the debate around ending alcohol prohibition (i.e. legalizing its distribution) in Ontario between 1920 and 1927. It then uses material drawn from a comprehensive search of the Canadian House of Commons debates on cannabis legalization between 2016 and 2018 to draw parallels with the debates around alcohol legalization in Ontario about 90 years earlier. Results: While alcohol and cannabis legalization occurred in very different social and political contexts, there are similarities in both the arguments in favor of ending prohibition (ineffectiveness at preventing consumption and collateral social harms) and post-legalization debates around regulation (most notably the optimal way to replace the illicit market). Conclusion: The Canadian cannabis legalization debates of the 2010s echo the alcohol legalization debates of the 1920s in remarkable and relevant ways. Ultimately the most striking parallel may be the extent to which the political leaders advocating for legalization emphasized that their policy was not liberalization, but more effective control.