O'Keefe , from Toronto , Ontario , established itself in Montreal by the purchase of some 20 breweries including Molson 's main competitors in Quebec , Dawes and Dow .
The first large industrial - scale breweries were founded by Englishmen like John Molson in 1786 .
O'Keefe , from Toronto , Ontario , established itself in Montreal by the purchase of some 20 breweries including John Molson 's main competitors in Quebec , Dawes and Dow .
The first large industrial - scale breweries were founded by Englishmen like John Molson in 1786 .