HBO's gangster drama Boardwalk Empire returns for its fourth season tonight at 9 p.m. As ever, the show goes to great lengths to capture the realities of Prohibition, and that includes using old slang and havings its characters speak about the big sociopolitical issues of the day. Unless you're a scholar of American history during the Roaring Twenties, you're going to encounter some moments during tonight's premiere where you'll wish you had more context.

Edutainment alert! There will be no spoilers about the action of tonight's episode in this piece, but you will learn a little something. This installment of Fact Check will elaborate on some locations mentioned or frequented in tonight's episode, define some slang and antiquated words, offer the history of a certain cocktail, and more. This way, you won't feel dumb watching Boardwalk Empire.

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