De Cive was published in 1642. It was neither the first nor the last of Hobbes's treatises on civil government. He came at the subject again and again, first in a manuscript intended for private circulation, The Elements of Law (1640), next in De Cive, once more in his best-known book, Leviathan (1651). Then there were writings in which the principles of politics provided the main subtext. One was A Dialogue Between a Philosopher and a Student of the Common Laws of England, complete by 1666 but only published after Hobbes's death in 1681. Here he pursued the question of the relative authority of the statute and the common law in terms provided by his theory of the rights of sovereigns. And in Behemoth, his history of the English Civil War, he used the same theory to relate the 'causes, pretensions, order, and artifice' of the events of 1640 to 1660.