(Red Wings; but more at Red Clay)
Today’s place name etymology is a pretty interesting one because we will get a sneak peak at the extinct pre-Edo Period dialect of the area. Akabane sits in the northern part of Kita Ward. It’s basically next to Kawakuchi, Saitama. So it’s on the literal outskirts of Tōkyō. Mind you, you won’t see any difference leaving Tōkyō and entering Saitama due to the thorough urban sprawl.
Historically speaking, 赤羽村 Akabane Mura Akabane Village wasn’t a particularly important place, but in the Kamakura Period a highway called 岩槻街道 Iwatsuki Kaidō was built. The road is better known by its Edo Era name, 日光御成街道 Nikkō O-nari Kaidō. As mentioned in my article on Tokugawa Ietsugu’s Mausoleum, 御成 o-nari refers to the presence of the shōgun. As such, this was a private highway for the shōgun family to use when visiting 日光東照宮 Nikkō Tōshō-gū. It was a shortcut that connected the 中仙道 Nakasendō to the 日光街道 Nikkō Kaidō. The road passed through Akabane and there was a rest station 宿場 shukuba at the next town, 岩淵宿 Iwabuchi Shuku Iwabuchi Post Station. That town was pretty important and well known. Akabane was just another small village in the country.
.OK. So now we have a little historical context for the city. Where does the name come from?
Well, if we strip away the kanji, we can find the origin of the name:
あか aka means red.
はね hane is the old local dialect word for 埴 hani, clay.
The 荒川 Arakawa River apparently deposited a lot of red colored volcanic ash from Mt. Fuji here. The buildup of this material produced a red slimy, claylike soil that was particular to the area. If an area eroded, the red clay would become exposed. Thus the area was called 赤埴 Akabani Red Clay. But in the local accent the name was pronounced Akabane. Later, as literacy rates improved in the area, the second kanji was changed to actually match the pronunciation. So 羽 hane wings was added, thus obscuring the origins of the place name as 赤羽 Akabane Red Wings.
For another sneak peak at the old dialect, we can look at the name of the highway that passed through here. It was called the 岩槻街道 Iwatsuki Kaidō. But place name 岩槻 Iwatsuki was originally written as 岩付 Iwatsuke. Diachronic Japanese linguists and dialectologists use evidence like this to track the development and differentiation of vowel quantities – in particular え /e/ and い /i/ which traditionally show great instability. So now you know.
Apparently, 赤羽橋 Akabanebashi (Red Wing Bridge) in Shiba (Minato Ward) has the same derivation. Archaeological findings in the postwar years confirmed the existence of medieval kilns and earthenware factories.
 But the most famous pre-Saitama of all is Ikebukuro.
 A family name and a place name Akahani still persists elsewhere in Japan and the kanji is consistent with the original writing of the of the name. The writing of Akahani instead of Akabani reflects a conservative pronunciation before the 連濁 rendaku sound changes of the Tōkyō area became the national standard.