HMS Erebus was discovered in 2014. HMS Terror was discovered, intact and in "incredibly good condition," in 2016 by Arctic Research Teams just before this show's premiere in March 2018. AMC's president responded publicly by stating " I congratulate the researchers find, however, apparently they never heard of a spoiler alert!"
Jared Harris was in such awe of the ensemble of actors in season 1, he routinely asked if some of his better lines could be given to them if it made sense for the narrative, comparing their talents to Lamborghinis sitting in a garage.
Both Jared Harris and Tobias Menzies have since proclaimed this series is one of the projects they are most proud of in their respective acting careers.
This was originally envisaged as a theatrical release with David Fincher directing.
For Season 1, Captain Francis Crozier is from Banbridge, Northern Ireland where a statue of him stands in the town centre.