I would say that Locke was influenced by Descartes.  While he might have held some fundamental disputes with Cartesian logic, the basic premise of the realm of the private is something that resonates quite loudly with Locke.  When Descartes derives the basic notion of existence as one that is predicated upon thought in the private interior of one's mind, it helps to establish the division between public and private, a division that plays a major role in Lockian thought.  The fact that this interior is where consicousness is in existence also helps to bring out Locke's idea of a "blank slate," where individual experiences end up comprising one's own sense of self.  At the same time, the public/ private division is where Locke firmly defines the role of government as being one that cannot trample on or enter into this realm or space.