Ikaris is a member of the Eternals, a near-immortal evolutionary offshoot of humanity created by the Celestials. He was born over twenty thousand years under another name which has not been revealed. When the cities of Atlantis and Lemuria were sunk in 18,500 B.C. by the Second Host of the Celestials in what is now known as the Great Cataclysm, Ikaris guided an ark of refuges to safety by flying high above them always watchful for ambushes, the humans aboard the ark mistook Ikaris for a bird, the tale eventually became part of human folklore. Around this time a Celestial committed some unknown crime while on Earth, and was punished by having its energies released from its armor, then forced into a deep slumber, buried by its fellow Celestials, where it became known as the “Dreaming Celestial”. The weapon used to disperse the Celestial and its essence are entombed within the Pyramid of the Four Winds, an Arctic facility built by Virako, Ikaris’ father. Ikaris is one of the few to know what the Pyramid contains.

Over the millennia, Ikaris became a constant opponent of the Deviants, a misshapen race who were also created by the Celestials, although most Eternals judged Ikaris as rather head-strong, his closest friends stood united at his side, among them: the speedster Makkari, the hedonistic Sersi, and Thena, daughter of their leader, Zuras. In ancient Greece, Ikaris (under another name) fell in love with a human woman, whose name has long been lost to history, but she bore him a son, whom she named Ikaris. The younger Ikaris not gaining the full power of an Eternal, wanted to fly with his father, so Makkari built the child a flight harness, which would enable the boy to fly on his own. The elder Ikaris was called away to battle the Deviants shortly thereafter, seeking to find his father and help him fight, the younger Ikaris flew to find him, but he soared to high and fainted from the lack of oxygen and lost control when the sun’s rays burnt the harness’ controls. Ikaris fell from the sky into the Ocean; Ikaris buried his son, and took the name Ikaris for his own to ensure that he would never forget. At some point in his lifetime, Ikaris became the sworn enemy of the long-lived mutant Apocalypse.

As the Eternals prepared for the coming of the Forth Host, Ikaris befriended Black Bolt, ruler of the Inhumans, another subspecies of humanity. During this time the Eternals assisted the Inhumans in moving their capital city of Attilan from the Atlantic Ocean to the Himalayan Mountains.

At the time of the Forth Host’s arrival on Earth, Ikaris adopted the human guise of “Ike Harris”; posing as a guide through the Andes Mountains for archeologist Dr. Daniel Damian and his daughter Margo. Ikaris led the Damians to the city of the Space Gods where the Third Celestial Host had been based. Ikaris awakened Ajak who served as the Eternal’s point man for the Celestial Host; he contacted the Host and they arrived in orbit of Earth. The Deviants attempted to interfere, but to no avail. Dr. Damian remained with Ajak; Ikaris introduced Margo to the world of the Eternals, and the two became lovers.

The Forth Celestial Host arrived soon after and the Eternal revealed their existence to humanity, but after judging in favor of life on Earth, the Celestials erased humanity’s memories of the event.

Many Eternals during this time chose to leave Earth and explore space, causing their numbers to dwindle on Earth. Zuras’ daughter became Prime Eternal in her father’s place (Zuras had been killed by the Forth Host), and Ikaris clashed with her over matters of authority, and when Ikaris became aware of a Deviant plot to awaken the Dreaming Celestial he challenged her for the position of Prime Eternal, feeling that Thena’s love of the Deviant Warlord Kro compromised her leadership. Ikaris won the title and aided by the Avengers was successful in defeating the Deviants, although Margo Damian was killed in the conflict. Ikaris buried her on an island where he had laid to rest dozens of other lovers over the centuries.

Margo’s death drove her father insane and he attempted to use Eternal technology to destroy both the Eternals and the Deviants. He was finally stopped and killed by his one-time friend Ajak. Later Ikaris was among the heroes who assisted Quasar in stopping the Starblasters in acquiring the Starbrand.

When Apocalypse further mutated the Deviants to make them run amok, Ikaris was forced to re-introduce the Eternals to humanity, although this time he called his people “the New Breed” and referred to himself as ‘Sovereign’.

Recently, seemingly suffering from partial memory loss, “Ike Harris” attempted to force “Mike Curry” that he was indeed Makkari. It was later revealed that Sprite (an eternally young Eternal) not only caused the memory loss, but caused the Dreaming Celestial to un-create the Eternals. Causing all Eternals to forget anything about themselves and lose all their abilities. Only Ikaris’ position as Prime Eternal allowed him to recall anything.

Sprite was defeated by the reformed Eternals.