Proper nouns tend to be taken for granted by language teachers. Basic knowledge regarding, for instance, the names of countries, is assumed to sort of enter by osmosis, and overlooking important language aspects such as spelling, pronunciation and even meaning. Just how do we pronounce Leicester or Leicestershire?
There are even false friends: is Jean a man's name or a woman's name? Joan in England is a woman's name, but for a Catalan, it's a man's name. Likewise, common familiar names can be confusing: Sam/Sammy? Billy/Billie? Areas such as "the East End" (He grew up in the East End) convey meaning to native speakers. but will probably mean nothing to a foreign student.