Stephan Scott Grundy (born 1967 in New York City, New York, United States), commonly known as Stephan Grundy, and also known by the pen-name Kveldulf Gundarsson, is an American author, scholar, goði and proponent of Asatru. Grundy grew up in Dallas in the U.S. state of Texas. He now lives in Shinrone, County Offaly, Ireland. He has over two dozen published books and a number of published papers. He is best known for his modern adaptations of legendary sagas and also a non-fiction writer on Germanic mythology, Germanic paganism, and Germanic neopaganism.