Which non-Anglo Saxon country would you say was more liberal than France during the age of liberalism? In France, men like Turgot, Say, Constant, and Bastiat were just the peaks of a great wave of liberal thought. In the German-speaking world, men like Humboldt, Goethe, and Menger were liberal anamolies. Even Kant, who is one of the few influential German thinkers one could characterize as liberal, did not understand the harmony of interests, as Mises wrote in Socialism:
The principle of the division of labour revealed the nature of the growth of society. Once the significance of the division of labour had been grasped, social knowledge developed at an extraordinary pace, as we see from a comparison between Kant and those who came after him. The doctrine of the division of labour as put forward by eighteenth-century economists, was far from fully developed when Kant wrote. It had yet to be made precise by the Ricardian Theory of International Trade. But the Doctrine of the Harmony of Interests had already anticipated its far-reaching application to social theory. Kant was untouched by these ideas.
In fact, although many people think of Mises as something of a Kantian, Mises largely blamed Kant for the methodological collectivism that made German social philosophy so barren for so long. He writes:
In economics as well as in general sociology [collectivism] has proved itself utterly barren. It is no accident that the German mind, dominated by the social theories of classical philosophy from Kant to Hegel, for a long time produced nothing important in economics, and that those who have broken the spell, first Thünen and Gossen, then the Austrians Carl Menger, Böhm-Bawerk, and Wieser, were free from any influence of the collectivist philosophy of the State.
Mises goes into more detail on Kant’s philosophy in chapter 2 of Socialism.