Boardwalk Empire is an American period crime drama television series created by Terence Winter for the premium cable channel HBO. The series is set chiefly in Atlantic City, New Jersey, during the Prohibition era of the 1920s. The series stars Steve Buscemi as Nucky Thompson. Winter, a Primetime Emmy Award-winning screenwriter and producer, created the show, inspired by Nelson Johnson's 2002 non-fiction book Boardwalk Empire: The Birth, High Times, and Corruption of Atlantic City, about the historical criminal kingpin Enoch L. Johnson.

The pilot episode was directed by Martin Scorsese and produced at a cost of $18 million. On September 1, 2009, HBO picked up the series for an additional 11 episodes. The series premiered on September 19, 2010, and its five-season run of 56 episodes ended on October 26, 2014.

Boardwalk Empire received widespread critical acclaim throughout its run, particularly for its visual style and basis on historical figures, as well as for Buscemi's lead performance. The series received 57 Primetime Emmy Award nominations, including two for Outstanding Drama Series, winning 20. The series also won the Golden Globe Award for Best Television Series – Drama in 2011 and two Screen Actors Guild Awards for Outstanding Performance by an Ensemble in a Drama Series in 2011 and 2012.