Ab urbe condita
Titus Livius (Livy)
Livy. History of Rome, Volumes 1-2. Roberts, Canon, Rev, translator. London, New York: J. M. Dent and Sons; E. P. Dutton and Co., 1912.
After a time the plebs began to murmur that their bondage was multiplied, for they had a hundred masters instead of one. It was evident that they would insist upon a king being elected, and elected by them.
When the senators became aware of this growing determination, they thought it better to offer spontaneously what they were bound to part with, so, as an act of grace, they committed the supreme power into the hands of the people, but in such a way that they did not give away more privilege than they retained.