NiziUNizi U dibentuk sebagai realisasi visi "[[K-pop]] 3.0" ala JYP Entertainment bertajuk "Globalization by Localization" (Globalisasi melalui Lokalisasi) melalui acara realitas bertema ''survival'', ''[[Nizi Project]]'',<ref>{{cite web|last=Seung-joon|first=Yang|url=https://www.hankookilbo.com/News/Read/201808201613343213|script-title=ko:“현지인 멤버로만 아이돌 구성” K팝 수출 3.0시대|website=[[Hankook Ilbo]]|language=ko|date=21 Agustus 2018|access-date=22 Agustus 2020|archive-url=https://www.hankookilbo.com/News/Read/201808201613343213/https://www.hankookilbo.com/News/Read/201808201613343213|archive-date=22 Agustus 2020|dead-url=no}}</ref><ref>{{cite web|last=Dong-woo|first=Chang|url=https://en.yna.co.kr/view/AEN20200713004900315|title=Exporting the template: K-pop agencies' overseas idol projects yield solid results|website=Yonhap News|date=13 Juli 2020|access-date=20 Juli 2020|archive-url=https://web.archive.org/web/20200719110620/https://en.yna.co.kr/view/AEN20200713004900315|archive-date=19 Juli 2020|dead-url=no}}</ref> yang ditayangkan secara ''streaming'' setiap minggu oleh [[Hulu]] Japan & kemudian ditayangkan untuk pemirsa internasional melalui akun Youtube resmi milik [[JYP Entertainment]].<ref>{{cite web|last=Hye-min|first=Hong|url=https://www.hankookilbo.com/News/Read/202005200829016558|script-title=ko:JYP 한일합작 오디션 ‘니지 프로젝트’ 파트2, 유튜브 방영 확정 [공식]|website=[[Hankook Ilbo]]|language=ko|date=20 Mei 2020|access-date=4 Juli 2020|archive-url=https://web.archive.org/web/20200704061210/https://www.hankookilbo.com/News/Read/202005200829016558|archive-date=4 Juli 2020|dead-url=no}}</ref> ''Nizi Project'' dibagi menjadi 2 musim. Musim pertama menampilkan audisi yang digelar di seantero Jepang untuk mencari anggota potensial, 9 menyisakan 14 dari 26 gadis yang dipilih oleh [[J. Y. Park]]. Musim ke 2 memperlihatkan gadis-gadis tersebut pindah ke Korea Selatan untuk dilatih selama 6 bulan.<ref>{{cite web|last=So-yeon|first=Yoon|url=https://koreajoongangdaily.joins.com/2020/05/20/kpop/nizi-project-japan-jyp-entertainment/20200520172700171.html|title=JYP Entertainment's "Nizi Project" is coming to YouTube|website=[[Korea JoongAng Daily]]|date=20 Mei 2020|access-date=31 Agustus 2020|archive-url=https://web.archive.org/web/20200520165410/https://koreajoongangdaily.joins.com/2020/05/20/kpop/nizi-project-japan-jyp-entertainment/20200520172700171.html|archive-date=20 Mei 2020|dead-url=no}}</ref>
Pada tanggal 26 Juni 2020, episode terakhir dari ''Nizi Project''—beserta anggota yang debut—diungkapkan kepada publik. Sebagai bagian dari JYP Entertainment, Nizi U akan bekerja sama dengan label rekaman Sony Music untuk menangani penjualan album dan& manajemen grup mereka selama beraktivitas di Jepang.<ref>{{cite web|last=Eon-kyeong|first=Shim|url=https://news.chosun.com/site/data/html_dir/2020/06/26/2020062601681.html|title=JYP '니지 프로젝트', 데뷔 멤버 9명 최종 확정..그룹명은 '니쥬'|website=The Chosun Ilbo|via=OSEN|language=ko|date=26 Juni 2020|access-date=30 Juni 2020|archive-url=https://web.archive.org/web/20200628220810/https://news.chosun.com/site/data/html_dir/2020/06/26/2020062601681.html|archive-date=28 Juni 2020|dead-url=no}}</ref><ref>{{cite web|last=Hye-min|first=Hong|url=https://www.hankookilbo.com/News/Read/A202006261106000005|script-title=ko:JYP 新 걸그룹은 '니쥬'...니지 프로젝트 멤버 9명 최종 확정|website=Hankook Ilbo|language=ko|date=26 Juni 2020|access-date=4 Juli 2020|archive-url=https://web.archive.org/web/20200704061123/https://www.hankookilbo.com/News/Read/A202006261106000005|archive-date=4 Juli 2020|dead-url=no}}</ref><ref>{{cite web|last=Jae-hoon|first=Lee|url=https://entertain.naver.com/read?oid=003&aid=0009936110|script-title=ko:박진영·JYP 표 일본걸그룹 탄생, '니쥬' 론칭|website=[[Naver]]|via=[[Newsis]]|language=ko|date=26 Juni 2020|access-date=4 Juli 2020|archive-url=https://web.archive.org/web/20200704064231/https://entertain.naver.com/read?oid=003&aid=0009936110|archive-date=4 Juli 2020|dead-url=no}}</ref>
=== 2020-sekarang: Pradebut dengan ''Make You Happy'' ===
