Occasionally, an enthusiastic researcher will embark on a quest to find information on obscure gaming facts, so it's surprising that one of the great unknowns in video game history is the U.S. release date for Super Mario Bros. on NES.
Considering the fact that this is one of the most successful and iconic video games in the history of the industry, it's fascinating that its U.S. release date is still a source of debate. As explained in great detail by writer Frank Cifaldi on Gamasutra, Nintendo's official release date of 18th October 1985 is contradicted by other evidence, mainly related to what games were available for the 'trial' launch of the NES in New York and the subsequent national release in 1986. Identifying whether Mario's iconic platformer was available in the New York trial release seems to be the key issue to resolve.
After extensive research that takes into account media and eye-witness reports alike, it seems that it's impossible to definitively say when Super Mario Bros. was first sold in the United States: though the article does seem to narrow down the possibilities. As well as getting the full details on Gamasutra, linked below, it's also worth reading an article from fan-site The Mushroom Kingdom, called 'Super Mario's Release Date is Missing!', which was one of the first attempts to solve the mystery once and for all.
It's amazing that such an important fact in the brief history of video gaming is unknown. In the unlikely event that any of you happen to have definitive evidence of this famous launch date, we'd love to hear about it.