Combination word of
Chiba,
prefecture east of
Tokyo, and
Ibaraki, prefecture
northeast of
Tokyo.
Chibaraki is used to make fun of Chiba, giving it a
connotation of being like or not any different from Ibaraki.
Well, why would being like Ibaraki be a put down? That is because Ibaraki is preceived as a totally rural and backwards prefecture full of hillbillies. For example, most people can't even pronounce the name of their home prefecture correctly (most Japanese for that matter anyway), it most always comes out as "IbaraGi". Come to mention it, pronouncing it as ChibaraGi might be even a bigger put down.
Most Japanese know the word Chibaraki, and no person from Chiba likes their home being compared to Ibaraki. But that is just the way the pecking order is in Kanto. Yeh, there goes your ideas of "Wa".
See also Dasaitama.