Career Resurrection: For Robin Wright, who had spent most of the 2000s in supporting or background roles in independent movies. House of Cards offered her a co-lead role in a mainstream product for the first time in several years, earning her a Golden Globe award as well as multiple Emmy nominations in the process. She was subsequently in more big-budget features (like Wonder Woman and Blade Runner 2049) as a result.
Name's the Same: Rather bizarrely, Doug Stamper is the only character to have the same last name as their British counterpart (Tim Stamper). Similarly, Francis Underwood is the only character to have the same first name as his British counterpart (Francis Urquhart), and Claire also always addresses him as "Francis"; everyone else addresses him as "Frank" because a Southern Gentleman named Francis would insist that you call him 'Frank', and a British aristocrat would faint at the idea.
Michel Gill (President Garrett Walker) is married to Jayne Atkinson (Secretary of State Catherine Durant).
Paul Sparks' (Thomas Yates) real-life wife Annie Parisse appears as a mother on the Iowa campaign trail.
Michael Kelly's (Doug Stamper) real-life daughter Franke and son Clinton make an appearance in Chapter 36 as Doug's niece and nephew. They even have the same names.
Role-Ending Misdemeanor: More like Show-Ending Misdemeanor. Following actor Anthony Rapp's allegation against Kevin Spacey that he sexually assaulted him when he was 14, Netflix first announced that the show will conclude with season six. They then suspended production on said season and fired Spacey after more accusations of sexual harassment and assault came out, including, most damningly, some from the set of the show itself.
Separated-at-Birth Casting: Kelly AuCoin, who plays Doug Stamper's brother Gary, seems to have been cast because he looks like a spitting image of Michael Kelly.
Troubled Production: Filming on Season 6 was interrupted by Anthony Rapp's accusation that Kevin Spacey molested him 30 years earlier, when he was fourteen. Netflix quickly announced that this would be the show's final season (though this was always the plan anyway), and shortly afterward shut down production indefinitely as similar stories about Spacey came pouring in. He was then sent for an unspecified "evaluation and treatment," throwing further doubt on whether the season would be completed. And then eight crew members came forward with accounts of Spacey's predatory behavior which made them deeply uncomfortable around him. Spacey was fired a week later.
Unintentional Period Piece: The presidency of Donald Trump caused many accusations that the show suddenly seemed completely irrelevant, with its depiction of an overtly evil president suddenly seeming downright quaint next to the real thing.
When Frank Underwood visits Petrov in the Jordan Valley in Chapter 36, the Navy SEAL security team riding in the Hummers with him are all real Navy SEALS that Kevin Spacey worked with on Captain Phillips (on which Spacey served as an executive producer). In particular, the Navy SEAL on his immediate left when Frank steps out of the vehicle is Spacey's actual bodyguard in real life.