Nobunaga Shimazaki is a Japanese voice actor born on December 6, 1988, in Miyagi Prefecture. He is affiliated with the talent agency Aoni Production. Shimazaki graduated from Aoni Juku, the training school operated by his agency. He decided to pursue a career in voice acting after being inspired by the performances of veteran voice actor Green River Light, whom he admired.

Shimazaki made his debut in 2009 with a small role in the television anime series Animal Detective Kiruminzoo. His first leading role came in 2012 when he was cast as Kaito Kirishima in the series Waiting in the Summer. This was followed by other significant roles in the same year, including Taichi Tanaka in Tari Tari and Kenji Nakanishi in Say I Love You.

His career advanced rapidly, and in 2013 he received the Best Rookie Actor Award at the 7th Seiyu Awards. He later won the Best Actor in a Supporting Role award at the 15th Seiyu Awards for his performance as Yuki Soma in the reboot of Fruits Basket. He has also received multiple nominations from the Anime Trending Awards for his voice acting and for being part of ensemble casts in series such as Fruits Basket and Astra Lost in Space.

Shimazaki has built an extensive filmography, voicing a wide range of characters across numerous popular anime series. He is known for his roles as Haruka Nanase in the Free! franchise, Shido Itsuka in the Date A Live series, and Yuki Soma in Fruits Basket. He also voices the protagonist Ritsuka Fujimaru in the Fate/Grand Order anime adaptations. In the action genre, he has taken on roles such as Mahito in Jujutsu Kaisen, Baki Hanma in the Baki series, and Eugeo in Sword Art Online: Alicization.

Other notable roles include Seishiro Nagi in Blue Lock, Rintaro Suna in Haikyu!! To The Top, Hyuse in World Trigger, Yuno in Black Clover, Satoru Furuya in Ace of Diamond, Shun Kaido in The Disastrous Life of Saiki K., and Izana Kurokawa in Tokyo Revengers: Tenjiku Arc. He has also voiced characters in popular films, such as Tsukasa Fujii in Makoto Shinkai's Your Name..

In addition to anime, Shimazaki has lent his voice to numerous video games. Some of his notable game roles include the male protagonist Corrin in Fire Emblem Fates, Wol in Mobius Final Fantasy, Naoto Kurogane in BlazBlue: Central Fiction, and Jamil in Granblue Fantasy. He also voices Silver in the mobile game Disney: Twisted-Wonderland.

Shimazaki is known for his deep enthusiasm for specific franchises. He is a well-known fan of the Fate series, particularly the mobile game Fate/Grand Order, in which he also voices the protagonist. His passion for the game is so well-known that his spending on it has been a topic of discussion among fans and colleagues. He is also an avid fan of the Love Live! multimedia project. He maintains close friendships with several fellow voice actors, most notably Yoshitsugu Matsuoka, with whom he has a long-standing and well-documented friendship. He announced his marriage on January 1, 2023.