Many houses in the area are so large that they're considered estates by Tokyo standards (houses in Tokyo are small). It's well known that celebrities, sports stars, politicians and business leaders live in Denenchofu (especially the 3-chome area).
Denenchofu was farmland when Japanese industrialist Shibusawa Eiichi purchased much of the area in 1907 for development1. Eiichi is known as the father of Japanese capitalism. He was involved in founding over 500 Japanese corporations — many of which are still amongst Japan's biggest companies today (e.g. Mizuho Financial Group).
Eiichi's idea: a garden suburb based on the garden communities of London2. His idea couldn't have been more timely. In 1907, Tokyo's population had just tripled (in less than 40 years) to 2.6 million people. Over crowding was becoming a serious issue. Tokyo had grown so quickly urban planning had always been a secondary concern.
Denenchofu was different: a well known British city planner was hired to design the area. Wide tree lined boulevards and parks were incorporated in Denenchofu's design.
Denenchofu really took off after the Great Kanto Earthquake of 1923. Much of Tokyo was destroyed. Denenchofu was left relatively untouched.
Today it's considered a good place to raise a family. There isn't much nightlife in the area. Quiet shops dot the neighborhood.
Denenchofu borders other posh residential neighbourhoods such as Jiyugaoka. It's on the Tamagawa river at the border between Tokyo and Kawasaki.
Denenchofu is no longer considered suburban. It's highly urbanized and close to central Tokyo. For example it's only 12 minutes from Shibuya by train.
Denenchofu is #5 of 21 best places to live in Tokyo.