Songfacts®:

• Grateful Dead lyricist Robert Hunter wrote the words for this song, as he did for most Dead songs. Jerry Garcia wrote the music.
  
  For years the legend was that "Bertha" was named after an old fan (an actual mechanical fan, not a fan of the music) that would jump around the Grateful Dead's office when turned on. David Dodd at the official Grateful Dead site clarified that old myth by citing an interview in which Hunter revealed that the Dead named the rambunctious fan after the song, rather than vice versa.
  
  What "Bertha" is actually about, Hunter believed (he claimed he couldn't remember for certain), is "some vaguer connotation of birth, death and reincarnation. Cycle of existences, some kind of nonsense like that."
  
  That origin story could make "Bertha" a pun for "birth." It definitely opens up fascinating new possibilities for the song.
• The simple surface interpretation of "Bertha" is that some unnamed character runs from a window, into a tree, and then into a bar, where he takes shelter from the rain. The song is fun and upbeat, so the silliness of the lyrics seems fitting. Going by Hunter's statement, though, the song is far more interesting that that.
  
  The song is then about a fellow going through the cycle of birth, death, and reincarnation. A simplified view on the Buddhist belief is that we have to keep cycling through lives until we achieve enlightenment, at which point we can get out of the run around and escape the game.
  
  So, in "Bertha," Garcia's saying (with Hunter's words) that he's tired of running through the birth-death-reincarnation cycle over and over again. If we look at "Bertha" as "birth," then the chorus:
  
  That why, if you please, I'm on my bendin' knees
  Bertha don't you come around here, anymore
  
  is a plea for escape from that cycle.
  
  Where things get really interesting is with the line "ducked back into a bar door," which could be play on the word "bardo." In Buddhism, bardo is the place or state-of-existence between two lives. You die, spend time in the bardo, and then are born again (unless you've achieved enlightenment).
  
  That interpretation clarifies why Garcia begs to be arrested.
  
  Ran into a rainstorm, I ducked back into a bardo
  It's all night pourin', but not a drop on me
  Test me, test me, test me, test me
  Why don't you arrest me? Throw me in to the jail house
  Lord, until the sun goes down, 'til it goes down
  
  What's really being asked for here is to be kept in the plane of the enlightened rather than spit back out on Earth to live life again.
• "Bertha" is the opening track on what's become known as the Skull & Roses album (it doesn't actually have an official name, after the record label refused the band's desire to title it Skull F--k), which is all live music. The version of "Bertha" on there was recorded on April 27, 1971, at the Fillmore East in New York City.
• In addition to the regular Dead band members, Merl Saunders played organ on this one. His friendship with Garcia and his appearance on this song and two others from the album ("Playing In The Band" and "Wharf Rat") helped launch a long, successful career in the music industry. He passed away in 2008.