The History of St Bernards

You can find many credible stories of the history of St Bernard's from the Smithsonian and available as collections on Wikipedia.

The history of St Bernard’s begins with Monks living in the Swiss Alps. They kept St Bernard’s to help rescue people in a snowy route called St Bernard’s Pass. The route passed through the Swiss Alps between Italy and Switzerland. The St Bernard’s were sent on rescue missions after bad snowstorms.  

They are estimated to have saved over 2000 people in snow rescues as they tolerate cold well and have a keen sense of smell. They were sent out in groups of 2 or 3 and used their ability to locate lost people and dig them out. They would then stay with the injured and lie on top of them keeping them warm until help arrived.
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https://www.smithsonianmag.com/travel/a-brief-history-of-the-st-bernard-rescue-dog-13787665/

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