Final answer:
A group of confederates, especially of states that are more or less permanently united, is best described as a federation. The Confederate States of America, formed in 1861, is a historical example of such a confederacy.
Step-by-step explanation:
To answer the question of what a group of confederates, especially of states, is called when they are more or less permanently united, we have several options. The correct term to describe this is a federation. A federation is a formal organization where states are members and usually have a central government for some purposes, such as defense, but retain autonomy in other areas. This concept is best illustrated by the creation of the Confederate States of America in February 1861. These seceded states drafted a constitution in Montgomery, Alabama, establishing a confederacy, with the intent to protect their autonomy and interests, such as the institution of slavery.