Sidenote: Happy anniversary, @dissociativity!
Warning, spoilers:
Since the lore explicitly states that the contamination reached “satisfactory global-level groundwater saturation” and “as government resources are strained to their absolute break point (globally, not just in the US)”, probably as well as the invasion, I’d assume that they did/are experiencing the same as the USA / New England.
However, if you don’t mind me, let me go into more details*…
*Disclaimer: The following section is not an official version (as theres is none, to my knowledge) and contains an extreme amount of stereotypes, so… don’t take it too seriously ?
It started with weird behavior of moose… mooses… meese?.. and bears in the form of elevated aggressions towards themselfs and other species (including humans).
Officials assumed it was an outbreak of a mutated form of the Chronic Wasting Disease (which the news ironically titled “zombie wave”) and ordered to look into it, eventually.
A few weeks after that, it started to show its effects on humans too. The amount of bar brawls increased nationwide. Multiple politicians and officials were attacked by an angry mob, and a lot of Poutine was thrown at them for no specific reason.
In an attempt to stop this “trend” and the unflattering pictures taken after the fact - which often found its way into social media - a temporary ban on Poutine was discussed.
The resulting backlash ended in a few riots all over Canada which quickly got disbanded by mounties who demanded the rioters to stop, in the uncommonly strong worded request ever heard: “I’m sorry to ask, but please stop this uncivilized behavior right now!”
The situation peaked when a single man - going by the name of Montoro Coureal Van Vertont - made the inexcusable misstep of not being sorry after acting out.
At this point, Canada realized that there was something horrible going on.
While they worked hard to figure out what was happening (even increasing the maximum working hours to 48.5 per week) it spiraled out of control all around the world.
When they saw the nukes hitting all over the USA (and the dead rising did also give it away), they knew it was only a matter of time until they would get wiped out too.
Soon portals opened and the “spontaniously appearing non-native without residency permit” (as “aliens” was to offensive and politically incorrect) poured out and invaded Canada.
The mounties couldn’t stop them, although there were proven cases of sannwrp’s who apparently got startled by the casual behavior of citizens who invited them to a talk, which they rudely turned down by turning around and walking right back through the portal.
In a last, desperate and mad attempt to slow down the invasion (probably made by at that point semi-feral decision makers), the government ordered to confiscate and use the strategic maple syrup reserves against the invaders. It turned out to be very effective, as it - indeed - did slow down the invaders who got stuck in the floods of tons of maple syrup.
…
But regardless… the same as all nations, Canada… fell.
The streets are now roamed by undead - sometimes really sticky ones…
And - occasionally - you can spot a zombie that kept a part of its identity… it’s muttering “'orry” once in a while when getting too close to an other zombie.