Historically, even when its masculinity was not explicitly asserted and women's exclusion. [contrarian]
Historically, even when its masculinity was not explicitly asserted and women's exclusion from the category was not overt, homo politicus from Aristotle through Kant and Hegel assumed a masculinist comportment and sphere of activity. Whether stipulated as participating in rule of the common (Aristotle), as paralleling military virtu (Machiavelli), as manly measure and fortitude (Weber), or simply as autonomy, rationality, and self-sovereignty (the moderns), homo politicus was almost always and expressly male.
Wendy Brown, Undoing the Demos, loc. 195