I came across this one while skimming the Monsters Manual: the Portuguese Man O' War. This made me all fuzzy inside because, frankly, I wasn't expecting it. In 800 years, almost 900 years, of history, Portugal left an indelible mark in the world's history. Portuguese influence is felt or seen in every corner of the world: from the introduction of advanced fire weapons in Japan to the many Portuguese-speaking cultures of Africa and South America. We developed the first metal astrolabe in Western Europe and Ferdinand Magellan initiated the first circumnavigation of Earth and his name was given to the Magellanic Clouds. At the height of Portuguese power on the seas, our navigators crossed every ocean on the planet and even faced terrible beasts with the help of the gods of Olympus in the immortal epic The Lusiads.
The Portuguese Man O' War is based on the creature of the same name, a jellyfish-like creature with poisonous tentacles. According to some sources, it takes its name from the floats that resemble the morion helmets of Portuguese soldiers of the 15th and 16th century. The appropriation of this creature by Gygax is interesting in that he never bothered to change the name to a more "fantasy-like" name. This would be consistent with the fact that initially, Gygax adapted real elements to his home campaign of Greyhawk. In the early days, even the Greyhawk map was simply Earth with the numbers filed off. It would be interesting to speculate why the name was left unchanged because the name itself anchors the creature in a real world culture, perhaps even breaking a bit the immersion. Nevertheless, on a pure historical point of view, this is a reminder that the Portuguese culture is deeply interwoven in multiple levels with other cultures, even if only in the most subtle and minute ways.