The Origins of Sex, By Faramierz Dabhoiwala

As gay marriage wins Westminster approval, this outstanding work of cultural history follows Britain's long, winding path towards sexual freedom.

Until the 17th century, Dabhoiwala argues, strict policing of personal morality (see Iran or Saudi Arabia today) was a European norm.

With Enlightenment, toleration slowly took root. So erotic choice required an intellectual revolution.

From brothel-keeping to sodomy trials, Restoration libertines to Georgian feminists, his book matches incisive scholarship with humane sensitivity.