Jun-ichi left in 2016, and the following year the band released their highest-charting studio album, Ultimate Sacrifice, which reached number 13.

[9] Galneryus was formed in 2001 by guitarist and bandleader Syu (Valkyr, Animetal, Aushvitz) and vocalist Masahiro "Yama-B" Yamaguchi (AxBites, Rekion, River End and Gunbridge).

[8][10] While at a live house in Kujō, Osaka, Syu heard fellow Kansai-native Yama-B on the radio and knew he wanted to work with him.

[11] Both veterans of the metal scene, Syu and Yama-B formed the band with the intention to "express both of their musical tastes/ideas" and so they started looking for additional members to complete the lineup.

They recruited A on keyboards (who had previously played with Syu in Valkyr), Shōgo Himuro on bass, and Toshihiro "Tossan" Yui (formerly of Cemetery, Honey Quest) on drums.

After playing with other metal bands like Fairy Mirror, Mephistopheles, Galactica Phantom, Mastermind, and Concerto Moon, Galneryus went back to the studio to record an EP.

[12] The EP again used support musicians to fill the band slots, with Shōgo Himuro again on bass, Toshihiro Yui again on drums, and Yoshinori Kataoka on keyboards.

[citation needed] Galneryus was also invited to perform on two metal compilation cover albums with other bands such as Masaki Project, Saber Tiger, and Mephistopheles.

Galneryus performed the song "Black Diamond" (originally from Finnish power metal band Stratovarius) on the compilation album Stand Proud!

Both compilation albums were released simultaneously in December 2002 on the same day through Iron Shock and distributed through the record label VAP.

VAP itself signed Galneryus and the band set to work on writing and recording their full-length debut album The Flag of Punishment which featured all 5 EP songs re-written and re-recorded and also cover art by famed Final Fantasy artist Yoshitaka Amano.

[10] At this time Galneryus ceased using temporary members and permanently recruited Ryosuke "Tsui" Matsui (formerly of AxBites) on bass, Yuhki (formerly of Ark Storm and Marge Litch) on keyboards and Jun-ichi Satoh (formerly of Concerto Moon) on drums.

After the Live for Rebirth tour, Tsui left Galneryus and Yu-To (later known as Leda of Deluhi, Far East Dizain, Kami Band)[14] was recruited to fill in for bass.

In February 2008, both sides of their double A-side single "Alsatia/Cause Disarray" were used as the opening and ending themes for the six-episode anime series Rin ~Daughters of Mnemosyne~.

[18] While Yama-B "likes to stick to a certain set of rules, concepts", particularly Syu would spontaneously abandon a style in order to incorporate new inspirations.

The title song was used in a Fist of the Blue Sky pachinko game,[25] and its cover features the series' main character.

(which was covered in English by Galneryus on Kizuna[25]) was previously the series' first opening theme, while a different version titled "Departure!

[28] On May 26, they performed at the Pure Rock Japan Live 2013 at Club Citta, alongside Nogod, Saber Tiger and Onmyo-Za.

[40] At the outset of the group, Yama-B and Syu wanted to stand out and so, among other things, wore armour and a red enamel outfit respectively.

[41] The songs on their first three albums tell a story,[43] and although he said Yama-B was better suited for the task, Syu briefly described it as the adventure of a man named Galneri.

[42] Yuhki composed its songs "Rain of Tears" and "Soul of the Field" specifically to utilize Syu's death growl.