The announcement that the Seibu department store in the Mullion twin building complex in Ginza will close at the end of the year has occasioned a lot of nostalgic ruminations in the media, even though the complex itself didn't open until 1984. Seibu is, relatively speaking, a youngster in the annals of the Japanese department store. The older, established stores, like Mitsukoshi, Matsuzakawa and Takashimaya, are still around (though struggling), which is really quite surprising since the whole department store paradigm became passé after the bubble era. If the younger stores like Seibu, Hankyu (which just announced it would soon close its iconic Kyoto store) and Tokyu are biting the dust before their elders it's mainly because their initial function had less to do with retail sales than with beefing up their respective owners' main businesses, namely railroads.
The older stores had their roots in the mercantile culture of old Edo or Nagoya or Osaka. The newer stores were built by railway companies that needed something that would make people use the trains on the weekends. Before the 1970s there were only small grocery stores and company-owned electronics dealers in the suburbs. For the full shopping experience, you had to get on the train and go to an urban center.
So railway companies bought land at main terminuses and built department stores there. Seibu's was Ikebukuro Station. These department stores thrived because once people started having disposable income in the the 1960s they wanted to spend it. So the companies built other department stores, and not necessarily at their own terminuses.