Series creator Sherwood Schwartz wrote the lyrics.

The words came before anything else. Schwartz was more than a writer. He had some musical skill, having learned the violin as a kid. Though he later admitted in his memoir, "The violin and I had an adversarial relationship." Schwartz could tap out a tune on the piano, at least, and he had some experience crafting theme songs. After all, he had previously written the lyrics for "The Ballad of Gilligan's Isle," the memorable theme to his earlier series, Gilligan's Island. 

Image: The Everett Collection

The theme nearly had a different composer.

Schwartz initially reached out to George Wyle to collaborate on The Brady Bunch in 1969. The two had struck a chord crafting "The Ballad of Gilligan's Island" together. However, Wyle could not accept the job. He was under contract to The Andy Williams Show. Schwartz instead reached into his Rolodex and contacted another songwriter he knew, one with prior sitcom theme success….

The composer made a cameo on the show.

Frank De Vol had been arranging music since his teen years. The musical ace carried a resume with credits including Nat King Cole, Ella Fitzgerald, Sarah Vaughan, Tony Bennett, Dinah Shore and Doris Day. His mood music LPs set the vibe in upscale bachelor pads. His scoring for Hollywood films had earned him four Oscar nominations, including one for Pillow Talk. Audiences everywhere were still humming his instrumental sitcom themes for My Three Sons and Family Affair. De Vol was a natural choice for The Brady Bunch theme. Schwartz even gave his composer some camera time. De Vol makes a cameo in season four's "The Show Must Go On??" He's the dad playing the saxophone at the school talent show.

There was nearly a last-minute name change.

The Wild Bunch nearly ruined everything. The bloody Warner Bros. Western raked in the bucks at the box office in the summer of '69. The studio behind The Brady Bunch panicked. "Paramount didn't want the negative word 'Bunch' associated with the Bradys," Schwartz recalled. "They were afraid the viewers would get the idea the show was a Western or about a mob." Schwartz, a lover of alliteration, suggested The Brady Brood. Because nothing better could be decided upon, they stuck with The Brady Bunch — and the rhyme with "hunch" stayed.

The pilot version was recorded by the Peppermint Trolley Company.

"The Brady Bunch" song is credited to Schwartz / De Vol, but to hear it from the performers, the band that recorded it deserves some credit. "[Our producer] Dan Dalton played us a tape of guy just speaking the words, Here’s a story, of a lovely lady… The recording didn’t really have the melody, or even the instrumentation," wrote Danny Faragher, vocalist-keyboard for the Peppermint Trolley Company. "We arranged it, and I can remember making up chords for it. We worked on the vocal parts, too." The Peppermint Trolley Company — and isn't that name that could only exist in the late 1960s? — had scored a minor hit the prior year with its sunshine bubblegum number "Baby You Come Rollin' Across My Mind." The group split shortly after the Brady session, as some members formed a new act dubbed Bones.

Three session musicians recorded the vocals heard in the first season.

The full Peppermint Trolley Co. version was used only in the pilot. The theme song heard throughout the first season had the band on the musical track, but the vocals had been redubbed by a trio of session singers. John Beland, an 18-year-old who had recently arrived in Hollywood, sang the final vocals with Paul Parrish and Lois Fletcher, as he remembered on his blog. Parrish was coming off a psychedelic soft-rock album recorded under his own name, titled The Forest of My Mind. Fletcher came from the folk scene, but more on her in a bit….

One of those singers wrote a tune for another TV star.

Paul Perrish's solo career might not have soared, but he did pen some memorable tunes for Helen Reddy, including "Time," the opening cut to her 1971 debut. That song was later covered by Sally Kellerman, "Hot Lips" from the MASH movie, the actress who had appeared in the second Star Trek pilot, "Where No Man Has Gone Before." She belts Perrish's "Time" on her 1972 album Roll with the Feelin'.

Image: Decca

One of those singers was in a folk band that played at the White House.

Lois Fletcher, the female voice heard harmonizing on the season one theme, was the wife of Dan Dalton, the aforementioned producer of the Peppermint Trolley Company. (He and the band had a falling out shortly after cutting "The Brady Bunch.") Fletcher and Dalton were part of a folk group called the Back Porch Majority. Their biggest claim to fame was entertaining Lyndon B. Johnson. In 1965, Time magazine invited the Majority to the White House, alongside The Brothers Four and The Bitter End Singers, to perform for the prez. That's Fletcher and Dalton circled in red on their 1965 LP.

The Brady Kids sang the theme from season two onwards.

Season two of The Brady Bunch arrived with an updated theme song. The Peppermint and session singers were gone, replaced by the youthful sound of the Brady kids themselves. As one legend has it, Christopher Knight was singing the theme on set during production, giving someone the idea to have the kids sing it. That may or may not be true. What is more certain is that The Partridge Family had arrived as competition in 1970. Seeing the money to be had with music product, the Brady producers put the actors in the studio as the Brady Six. The sextet recorded multiple albums, starting with a Christmas platter, and toured together. Their musical skills would carry over on the spin-off variety show, The Brady Bunch Hour.