The Mother Goose and Grimm strip of 12/3/15 (lots of stuff hangs around on my desktop for a really long time), depicting a canine guardian of the gates of dog heaven:
The definite article of uniqueness, here distinguishing a proper name St. Bernard (unique in some salient world for the user and their audience), the name of a specific saint, from a common noun St. Bernard (a type name), the name of a breed of dogs
Now it turns out that this usage can be employed to distinguish two proper nouns (according to their salience in a particular sociocultural context); and to distinguish two common nouns (picking out the salient type, rather than naming an individual). (Necessarily rather complex) examples follow.