Caskets for the show are made by ABC Caskets in Los Angeles.
Peter Krause (Nate Fisher) originally auditioned for the part of David, as he was impressed by the political/human rights message that the role had and he wanted to stand up for the character. However, the creator, Alan Ball had found the role of Nate Fisher impossible to cast, and was impressed by Krause and his tangible chemistry with Rachel Griffiths (Brenda Chenowith).
Within a week of the first episode being aired, HBO renewed the show for a second season.
In the credits of the pilot, you see a pallbearer who has a skeleton ring on his finger. The ring was digitally-erased from the credit opening thereafter.
The pilot episode features several spoof commercials for funeral homes and products. This was intended to be a recurring feature throughout the series but was dropped after the first episode.
Unusually, the title sequence was created after the theme music had been composed (generally, it's the other way round).
Alan Ball was inspired to write this series after losing his sister.
The lone tree in the opening sequence does not actually stand on the hill shown. It was dug up from someone's back yard, and placed there for the purposes of capturing the shot.
Set in Los Angeles because, according to series creator Alan Ball, LA is the "world capital of the denial of death".
Fisher & Sons funeral home is actually the well-known Auguste R. Marquis residence that now houses the Filipino Federation of America in Los Angeles.
Michael C. Hall's first screen role. He had confined himself to the New York stage prior to "Six Feet Under". The first scene he shot was in the pilot episode when David goes to the morgue to collect his father's body.
Rachel Griffiths had read the script and had indicated to the production that she was very interested in playing Brenda. The producers' only real concern was whether she could pull off a convincing American accent. When Griffiths flew over from Australia to meet them, she arrived complete with perfect accent, and got the part.
Dina Waters, who plays David's wannabe girlfriend Tracy in the first season, tested for the part of Brenda.
Alan Ball had 13 days to shoot the pilot episode, something which caused him a degree of anxiety, seeing as he had never directed before.
Kathy Bates, who directed two episodes in Season 1, would appear in an acting capacity from Season 3 on as Ruth's friend Bettina.
Nikolai's flower shop actually is a real flower shop at 14325 Ventura Blvd and was once a gas station. It was in fact the gas station that James Dean filled up at the day he left out of town on his way to the crash that would kill him (there is a color photo of him at the station about to get back behind the wheel in fact).
Alan Ball's cousin suffered from an arteriovenous malformation, which was the inspiration for the same ailment that afflicts Nate at the end of the first season.
Alan Ball specifically wrote the role of Federico Diaz for actor 'Freddy Rodriguez'.
The difference in ages among the Fisher siblings differs somewhat from that of the actors who portrayed them: Nate was born in 1965, like actor Peter Krause; but David was born in 1968, while Michael C. Hall was born in 1971; Claire was born in 1983, while Lauren Ambrose was born in 1978. So, while there's a 14/18-year hiatus between the births of the brothers and the sister as characters (and it's relevant to the story), the actors' actual birth dates are roughly equidistant.
Ranked #27 on Empire magazine's 50 Greatest TV Shows Of All Time (2008).
SPOILER: Both actresses who played Nate's mothers-in-law starred in Ridley Scott's cult science fiction movies. Veronica Cartwright (Peg Kimmel) played helmsman Lambert in Alien and Joanna Cassidy (Margaret Chenowith) played replicant Zhora in Blade Runner.
Anna Faris auditioned for the role of Claire Fisher, but according to Faris she was laughed off by the casting director.
Nate's middle name is Samuel.
Richard Jenkins and Frances Conroy previously played a married couple in Alex Haley's Queen.
The pilot's opening death was the only one not to be announced by an obituary, since it was Nathaniel's death that set the series in motion, and also because the mock funeral product ads took up screen time.
According to the Six Feet Under obituaries, Nathaniel Samuel Fisher's, the only one never to be shown on the show, is 1943-2000 (though it was mistyped to read 2001, the year which the first season's other deaths occurred in after New Year's).
Eric Balfour was only supposed to be introduced as "Claire's Meth Date" for the show's pilot, but the director found his chemistry so satisfying with Lauren Ambrose that his role was developed into the character Gabe Dimas. Similarly, Dina Waters's and Gary Hershberger's roles were only listed as "Chatty Mourner" and "Kroehner Representative (though the latter was already identified by the name Matthew Gilardi in the episode).