John Locke philosophized in the midst of political action. From 1683 to 1690, he spent the last years of the Stuart monarchy in continental exile. Charles II died in 1685, opening Britain's royal succession to a Catholic, James II. But resistance from a largely Protestant Parliament, backed by London financiers and a generally anti-Catholic English population, brought on a succession crisis. In 1688, invited by English magnates, William of Orange (husband of Mary, James's Protestant daughter, and chief executive of the Netherlands) invaded the British Isles. The ensuing civil war continued until 1691. In retrospect, people called the transfer of power to William and Mary the Glorious Revolution. In 1690, Locke accompanied Queen Mary on the ship that brought her from Holland back to England. He brought with him a manuscript, composed in exile, destined to be a founding document of the new regime: his Treatise of Civil Government.

Locke stated a contract theory of government with exceptional clarity and force. Government, he declared, rested ultimately on property and on consent of the governed. A viable vision of relations between rulers and ruled required a legislature – read Parliament – that spoke for the people, or at least for propertied men. The executive – read the Crown – enjoyed some autonomy, but ultimately remained subordinate to the legislature. Yet the supply of funds to support the executive's action posed a problem.