the zealous adoration of and interest in Liberal Leader and later long-term Prime Minister Pierre Elliott Trudeau, especially during the federal election of 1968.
2 n. — Politics
the enthusiasm in the wake of the election of Justin Trudeau, son of Pierre Elliott Trudeau, as the Canadian prime minister in the fall of 2015.
Type: 4. Culturally Significant — Trudeaumania was about more than a charismatic Pierre Elliott Trudeau; it was about Canada coming of age on the international stage and having something as cool, or cooler, in politics than the big neighbour to the south. The second wave of Trudeaumania must be read in the context of the autumn of 2015. After 10 years of an unimaginative and isolationist conservative government being in power, the younger Trudeau, against the odds, won the General Election of 2015 and triggered what is called in some places Trudeaumania 2.0 (see the 2012 quotation and the 2015 quotations).
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Chart 1: Internet Domain Search, 12 Oct. 2012