Final answer:
The Oklahoma Constitution was unique for being the longest constitution written among state constitutions at the time.
Step-by-step explanation:
The unique aspect about the Oklahoma Constitution is that it was the longest constitution that had yet been written at the time of its adoption.
Unlike the national U.S. Constitution, which is known for its brevity at just over 4,500 words, state constitutions are generally much longer and more specific, and the Oklahoma Constitution was no exception.
This length is a result of the details included in state constitutions about the structure, role, and financing of state and local levels of government.
State constitutions are often heavily amended or changed, indicating their more fluid and detailed nature compared to the relatively stable and concise U.S. Constitution.