Sure! Here goes. Note that the standard background and theme choices below are options all characters have in 4E, not only for flavor purposes but especially for their mechanical benefits. I realize parts of this will need to change to fit Athas, so I'm looking for guidance from those with more experience with the setting than I in ways to tweak the following to fit in with the setting.
Background: The East Rift consists of a country-sized shelf overlooking a cavernous abyss. Waters from various seas spill down from the heights, forming rapids and sparkling falls that tumble into the darkness below. Suspended in the air are curious motes, clumps of earth and stone that are crawling with strange creatures, wormed with tunnels, and laden with relics from the not-so-distant past. The East Rift is a wondrous place, with cunningly crafted switchback stairs, twisting pathways, and trained griffon steeds that all serve to connect the tiny communities that cling to the wounded stone.
Benefit: You gain Deep Speech as an additional language, you add Dungeoneering to your class skill list, and you gain a +2 bonus to Dungeoneering checks.
Theme: History litters the worlds featured in the Dungeons & Dragons® game. Old statues of people long forgotten stand in mute battle against the creepers and overgrowth. Crumbling ruins, toppled walls, and cracked buildings that are now home to the creatures of the wild still echo with the drama that once unfolded there. Even the dungeons that adventurers explore—built for reasons long lost, for purposes now inscrutable—can trace their origins back to the murky times gone by. The past is all around—in the wreckage of fallen kingdoms and empires, in the memorials raised to commemorate significant people and events, and in the names of heroes and villains that still resound through the centuries. For most, history is what has already happened—the events that have shaped the present. But for you, history was yesterday.
Born in an age far removed from the present, you were a member of the civlizations that transformed the world. You might have dwelled among the fiends of Bael Turath or the dragons of Arkhosia, taken leisurely strolls within the stunning city of Myth Drannor, or fought bravely amid the armies of the goblinoid Empire of Dhakaan. You witnessed these nations at their heights, when their lights shone the brightest, and you experienced the incredible grandeur and majesty of your civilization. Everything seemed possible.
But now, you are here—or, to be more precise, you are now, stuck in the current and very dark age. How did you come to be here and now? Perhaps it was an accident. Perhaps you were placed in stasis as punishment for crimes you did or didn’t commit, or as part of a magical experiment into the nature of time. Some magical calamity might have flung you forward, hurling you through the long centuries to emerge in a world far removed from the one you remember. However you made the journey, you now inhabit a changed world. The people you knew are bones and dust. The cities you loved so well are now reduced to monster-infested ruins. The life you led is a fading memory that only you recall.
Now you must make a choice. Do you lament the past you lost and curse this unforeseen future, or do you embrace this new, savage world? Or, perhaps, will you try to recapture the light that was lost and restore your old, forgotten realm? Only this time, under your guidance, the empire might stand the test of time.
Ghost of the Past Starting Feature (1st level): You gain training in History. If you are already trained in History, choose a different skill. Add the language of your fallen empire to the languages you can speak, read, and write. Finally, you gain the guidance of the past power.
One thing we were bandying about was the possibility that this druid had some sort of mystical experience connecting her to a spirit from Athas's Green Age, similarly to the experiences Buffy has with the spirit of the first Slayer in season seven of Buffy the Vampire Slayer, should you be familiar with that TV show.
Again, any help with placing this druid within the geography of Athas or suggesting ways to blend some of these elements from a canonical perspective is greatly appreciated!