[トピックス]「シオカラーズ」がリアルで歌って踊る「Splatoonシオカラライブ2016」開催決定！『Splatoon（スプラトゥーン）』の日本国内販売本数が100万本突破！ https://t.co/tnWCDNO9Df pic.twitter.com/Df64TDMnDO

— 任天堂株式会社 (@Nintendo) December 16, 2015

https://topics.nintendo.co.jp/c/article/918bb1fb-a221-11e5-a02c-0a6d14145cb1.html

Japanese tweet, here's a terrible google translate from the article:

Although it is the "Splatoon", finally unit sales in Japan (sell-through) is we topped one million ※ .This time, it also can hold such live events, and thanks to everyone and give to those who are seeking support to "Splatoon". Thank you very much.

Well, it did it, it passed the million mark in Japan in less than a year. This might be the best selling home console game in Japan this generation, only real contender is FFXV.

Damn, very nice. Congrat Nintendo!
Now the only game that can beat this is probably FFVII Remake.

YAY!!!!!!!!!
Nintendo did really hit the ball out of the park with this one!!!!
How they handled the free Content and the Marketing for this game really amaze me!
Splatoon has a birght future ahead!

Fresh!

Well deserved!
It will pass 3m WW at end of year.

That's what you get when you advertise your products properly. Congrats!

I really doubt that Code Name: S.T.E.A.M would sell 1m in Japan only if they advertise it properly. :)

This could actually be the best selling console game of the 8th generation. The only two games that I think can realistically compete with Splatoon at this point is Final Fantasy XV and Final Fantasy VII: Remake.

Good lord, how far this game has gone....
It has gone from the majority of people predicting it would bomb worse than Wonderful 101..... To outselling Halo 5: Guardians on the week of Black Friday... to competing with one of the most popular, classic, iconic franchises in gaming history... in its highest selling region...all while being a brand new Intellectual Property on the worst selling Nintendo console in history.
Imagine if the NX is a success and then the sequel comes out... Good Lord have Mercy.

Poor Codename S.T.E.A.M. Every single aspect of that game works against it, and it's specially tragic because with a few changes they could have gotten a decent and popular game.