Like many stories of food history, the exact creator is unknown, but there is usually one generally accepted story of origin. This story about the London Fog takes place in the now closed Buckwheat Cafe in Vancouver. A regular customer named Mary Loria was pregnant and could no longer drink coffee, so she asked for an alternative to her daily brew and received a concoction of steamed milk with Earl Grey tea and a little vanilla, which became commonly known as a London Fog.
By the mid-2000s, the drink became commonly ordered in Calgary, as it's noted that Vancouver's Loria would frequently visit family there and likely encouraged the ordering of this drink. Following that, it was added to the menus of major coffee shop chains like Starbucks and Second Cup, and gained mass appeal across the country.
Although it is primarily ordered at coffee shops across North America–in Scotland, they call in a "Vancouver Fog"–it is also very easy to make at home. Perfect for a rainy day, adding a splash of amaretto can make the London Fog extra comforting.