Daniel McCarthy, In the Name of Liberalism:

We could plunge deep into British history from here. Instead, I’ll make two general points: first, while there is a genealogical connection between Whiggism, liberalism, and libertarianism, the bloodlines are hardly unmixed or without bastards in each generation; and second, there is a recurrent problem when a faction that professes to be the party of liberty, whether it calls itself liberal or conservative or something else, takes control of the state and then comes to be opposed by another faction that claims to speak for liberty. For a time, the new faction can assert itself to be the true Whigs or real liberals, but pretty soon the confusion that results creates a pressure for a change of names. At that point, the new anti-statists might lay claim to an old label, such as conservative, or invent a new one, such as libertarian. Famously, when Friedrich Hayek was confronted by a situation in which “liberal” had been appropriated by social democrats and “conservative” had been taken by Russell Kirk, he tried to recover the “Old Whig” persona, but that didn’t catch on.