Not all the residents of the Astral Plane are native to that plane originally. Spirits of heroes and villains live there, those strong enough in spirit or with enough of a following on the Mortal Plane to find safe anchor in the turbulent astral sea. Many gravitate to the service of one of the The Heavenly Congregation while others serve along side the The Celestial Host; yet others find a home with the infernal Families. A few, those who have an independent source of anima--usually from mortal worship, carve out their own mini-demesnes from the chaos. Collectively, these souls are called the Celestial Chorus, individually they are the Ascended.
Demigods, Ascended Heroes, and Contractors
The Ascended fall into one of three groups, depending on how they made the leap from the Shadows into the Astral Plane and how they survive there. In almost every case, the ascended individual takes a new name or title.
Demigods--Those Chosen by a Congregant
Demigods are those who were raised up out of the Shadows after death (or very occasionally before death) by one of the 16 major gods. They then repay this act of grace by working for (and being fed by) the sponsoring god. Clerics and paladins are the most likely to become demigods.
One notable demigoddess is Mercy's Handmaid. One of the group of heroes that helped found the Council Lands, she served the former goddess of mercy and healing. When Melara took up her place in 48 AC, the Handmaid (in life a fallen deva cleric by the name of Merf) devoted the remainder of that mortal reincarnation to Her service, spreading the word of the arisen goddess of mercy and natural endings. When her mortal life ended, she could have returned to the Host and continued there, but she chose to accept the Lady of Mercy's invitation to stand at Her right hand.
Ascended Heroes--Self-made Men and Women
Unlike demigods, no deific hand was involved in the ascension of these powerful souls. They made the journey across liminal Shadow into Astral brightness on the wings of the worship of mortals (often their descendants) or under their own strength. They work as astral mercenaries, hunters, and adventurers. They handle the jobs that are too small (or too subtle) for the First Legion, First Host and occasionally manifest on the Mortal plane to assist their worshipers. Some live in the wild places of the Astral sea, subsisting on the anima of astral beasts. Their former occupations cover the scale, including warriors, mages, monks, and many other types.
One notable ascended hero is the Queen Ascendant. Formerly the queen of the Stone Throne, she was the living ritual focus for an ancient magical pact between her power-hungry eladrin father the Demon Prince known as the White Skull. The blood sacrifices and worship of her entire nation were channeled through her to the maw of the Demon Prince. She retained quite a lot of that power as a side effect. When the pact was shattered in 204 AC by the Catalysts, so too were the spells that kept her alive over the centuries. As her body failed, she drew on the worship of her people and the retained soul fragments to catapult herself past the Shadow threshold entirely and carve out a residence in the Astral. She is maintained by the faith and prayers of her people and acts as the spirit guide to the Queen's Fang who rules in her place.
The last group, the contractors, ascended as the result of bargains made during life. Bargains with powerful members of the infernal Families, they pledged their service after death and had the strength of spirit to withstand the process. These contractors are prized because they can more easily transition between the planes and draw much less attention on the mortal plane. They can visit at will, unlike the native fiends who must be summoned. It is said that much of the contractor's humanity is lost in the process, but those who are willing to make this deal usually don't care. Most often contractors were arcanists in life--warlocks, wizards, and sorcerers. Rarely they are bards, and only extremely rarely are they users of divine magics.