Denmark was a powerful Viking center which ruled much of Scandinavia, and even England, during the Middle Ages. Today it’s a constitutional monarchy which produces high-quality postage stamps. (Denmark’s autonomous regions – Greenland and Faroe Islands – each issue their own stamps. King Christian IV established the National Postal Service of Denmark in 1624, but its first stamp wasn’t issued until 1851. It bore the letters KGL which means “royal” in Danish. A block of four of Denmark’s second stamp (blue 2 rigsbank skillings) was sold at auction in 2011 for over $250,000. In 2014, Denmark issued a 9k stamp with a die-cut center left blank so the sender could write greetings!