Given your role as an educator, can I assume you are sufficiently aware of the endless debates on social contract and this useful package on Rousseau? Obviously, we are not here to discuss Enlightenment philosophies but it provides a framework to view this answer (a certain perspective).
The short answer is: Yes, there were. The steppe nomads (semi-nomads, to be more precise). The caveat is you must agree with the work of Dr David Sneath because he made this argument in his book, The Headless State - Aristocratic Orders, Kinship Society, and Misrepresentations of Nomadic Inner Asia (Columbia University Press, 2007).
From the site introduction (same link above) of the book - emphasis mine:
Sneath argues that aristocratic power and statelike processes of administration were the true organizers of life on the steppe. Rethinking the traditional dichotomy between state and nonstate societies, Sneath conceives of a "headless state" in which a configuration of statelike power was formed by the horizontal relations among power holders and was reproduced with or without an overarching ruler or central "head." In other words, almost all of the operations of state power existed at the local level, virtually independent of central bureaucratic authority.
In essence, Sneath's argument is, from a perspective of nomadic feudalism, steppe-nomads were highly egalitarian and much depended on alliances that are highly adaptive to changing demands. Hence, the social control (or oppression, depending on which strata you're in) is minimal (did not exist?) but steppe culture/societies still functioned well (i'm over-simplifying the book).
NOTE: I should add that this book was not well-accepted, especially with established scholars (specialists in Central Asia) - see reviews from Barfield (anthropologist), Nikolay Kradin (anthropologist and archaeologist) and Peter B. Golden (historian).
In defence of Sneath, however, we should note that he has studied under (worked with?) the late Urgugne Onon, who had direct experience of nomadic life as well as translating Genghis Khan's Secret History of the Mongols.