The Oakspines: bridge builders enabling colonization

[Prompt: A powerful organization in your world]
(Note: Because I need to go back and lay a lot of historical groundwork for Acorn's story, every part of this is extremely tentative and subject to change. Consider it self-fanfiction.) Oakbones name explanation
The first of the nation's great architects was Scattered Acorns of Oaks Island. The "oak" half of the name pays homage to her island and her own paws. Though Acorn came from a plant-coaxing line, her powers centered around shaping stone, calcium, and other inorganic materials. She used those powers to build bridges: floating, ornate, massive. Thus, the terrestrial skitters gained access to other islands, something only the much-smaller set of swimmers and flyers could theretofore do. Over the course of her life, Acorn gained great status and command of a small army of builders and architects, which built hundreds of bridges and other structures under Acorn's direction.
When Acorn died, her builders placed her bones into the in-progress, biggest bridge yet. She had had the power to shape bone in life, and her character strength had supported the colonies. Some skitters commented on the importance of a backbone for supporting the whole body. Bones and spines were a very important theme to these builders. Thus, they christened both the bridge and themselves Oakspine. Acorn would forever help uphold the greatness of the nation.
(Aside: "her own paws" refers to her as an individual, drawing attention to the part of her body most useful to the colonies.)
(Note to future self: Maybe one of Acorn's descendants will be an accomplished chemist. If they inherit her powers or something like them, they will be uniquely sensitive to the chemical properties of different solid elements.)
With the help of these myriad bridges, the skitters colonized vast swaths of the Fractaling Islands. Naturally, the Oakspines' indispensable role in creating & maintaining these bridges grants them a lot of power, such that they have massive political influence over the islands. Expansion and building is in their interest; as long as they maintain their power, the colonies will keep building bridges. As long as there are places to expand and materials to build, the Oakspines will have power.
Acorn's spirit, adverbally, wouldn't approve. In the latter half of her life, she came to have a change of heart about expansion and the role of her craft in the colonies' ways. She was a staunch opposite to power for much of her life. Were she to see such a politically slippery group acting in her name to condense even more power in few jaws, it might kill her all over again.