He was a Shadow Angel before he fell in love with Celiane. He was murdered by Scorpius, but his soul was grafted into the Aquarion, earning him the title of Solar Wing. In the first episode he was the one who taught Apollo how to Union, and would sometimes help him pilot the Aquarion.
12,000 years prior to the original Aquarion series (24,000 before Aquarion EVOL) Apollonius was known as the Angel of Massacre who, along side his twin brother and "Love" Toma, harvested Humans for their prana to feed the Tree of Life and in turn the Shadow Angels. Though not much is know as to the events of this time, at some point Humans lead a retaliation effort against the Angels for their own freedom. This revolt was lead by the royal family of that time, Prince Scorpius and Princess Celiane (in the orginal anime Scorpius is never mentioned but has his name erased from the book of genesis). As the war went on eventually Apollonius and Celiane would meet in battle (in the OVA Scorpius was overseeing the fight), at some point soon after they would fall in love, causing Apollonius to betray the Shadow Angels and join the side of the Humans (along with his trusted and loved pet Pollon ). Apollonius would go on the learn and study humans including a trip to the beach with Celiane and to a withered farm with Scorpius (distinct memories for both royals in their later lives).
At an unknown point after Apollonius was captured by the Shadow Angels along with Celiane, pinned by his wings to a wall. Toma & Moroha wer ordered to exceute Apollonius and Celiane, at which point Toma barted sparing celianes life for Apollonius's return. Celiane responded in disgust causing Moroha to attempt to kill her, but before he could stike Celiane Apollonius ripped himself from his pined wings to save her. Shocked by his shedding of his wings, the Shadow Angels took it as his ultimate disgrace and made the severed wings into a helmet (worn by toma, though possibly out of his obsession rather than hatred). Later Apollonius would forge the Mechanical Angel Aquarion with the humans and defeat the Shadow Angels and seal Atlandia. It is unkown how the war came to its end in detail, but the results tore Celianes soul in two parts and merged part of Apollonius' soul with Aquarion whilst the other part was reborn, Scorpius and Pollon were also reborn. In the OVA it is revealed that Scorpius, who longed after the power of the Angel's wings, stabbed Apollonius with his sword on seeing the destruction of Atlandia (where Scorpius thought he could gain wings), though this tormented him onwards till his next life.
Aquarion's future deverges at this point, in the original anime and it's sequel the Mecha was found by DEVA and used to combat the Shadow Angels prior to the series begining, where in the OVA it was hidden under the forest Apollo was raised in with his grandfather and awakened when Toma attacked the forest.
Since he is a shadow angel he has many powers.He is shown to fly even without his wings as stated by Apollo.
His lover and partner, he was willing to betray his own group for their love and even stripped off his wings to save Celiane.
Pollon was his close companion, so devoted that he would join Apollonius in exile. In their subsequent reincarnations, they have remained allies, though their later relationships are never as close as their original.
Scorpius looked up to Apollonius and believed that the wings of the Shadow Angels could help mankind. Eventually he would become jealous of Apollonius and desire wings for himself, leading him to murder Apollonius in a failed attempt to prevent Atlandia from being destroyed and the last Shadow Angel feathers being lost to him.
Toma was Apollonius' old partner and twin soul. Toma fell in love with Apollonius and they promised to be together forever until the Tree of Life is in shambles. In the end he saved Celiane to make Apollonius come back to him, however he refused and stayed with Celiane and destroyed Atlandia with Aquarion.
- Whilst initially Amata Sora was considered Apollonius' reincarnation due to his possessing the Wings of the Sun, it was revealed by Mykage in episode 26 of Aquarion EVOL that Gen Fudou (in this time appearing as Zen Fudo) was infact the reincarnation.
- In episode 25 of Genesis of Aquarion, Toma revealed that he himself is apollonius's twin.