A bear sits in a dark cave, chewing garlic and mugwort for a hundred days. Hwanung (환웅) waits outside, watching to see if the animal will turn into a person.
The story goes like this. Hwanung came down from heaven to Mount Taebaek (태백산) and set up a little divine city. A tiger and a bear asked to become human. The tiger bailed. The bear stayed in a cave, ate only garlic and mugwort, and after 100 days became a woman called Ungnyeo (웅녀). She had a son, Dangun (단군), who became the first ruler of Joseon.
We only get the full tell in the 13th century book Samguk Yusa (삼국유사), written by the monk Il-yeon (일연). That's a long time after the supposed event, and the monk added details like the 100 days and the garlic test. The date 2333 BCE for Dangun's founding comes from texts like these, which mixed local story, Buddhist frames, and a taste for exact dates.
Archaeology tells a different, messier story. By the first millennium BCE you see bronze daggers, hill forts, and big dolmen cemeteries across the peninsula and Manchuria. Those finds show groups that could organize war, trade, and tribute, which is what a state looks like. Still, there's no single inscription that says "Dangun ruled here," which is why historians treat the myth as a seed for real politics.
The myth kept changing and got weaponized. In the colonial era Korean thinkers like Shin Chaeho (신채호) used Dangun to build a deep national past. The modern holiday Gaecheonjeol (개천절), on October 3, marks the legend's founding day and most kids learn the tale in school. The bear and the garlic stayed in the story because people needed a simple, proud origin they could point to.
So yeah, Korea's origin story features a bear that ate garlic and became a queen, and that tale still runs through schoolbooks and national holidays. It's wild, and it's also how people make a history they can wear on their sleeve.