What was the popular moral philosophy at the time when Kant lived?

Question

On Wikipedia it is said:

In Section II, Kant starts from scratch and attempts to move from popular moral philosophy to a metaphysics of morals.

Therefore, there was some kind of popular moral philosophy at those times. Probably it is not different from currently popular moral philosophy, but has anyone made an effort to show what was morally popular? If so, what were them?

I am interested in particularly pre-Kantian moral philosophy, because it was the first (accepted by academics) formulated in our era. Previous accepted by academics moral philosophy is virtue ethics, but it was kind of forgotten by the time when Kant lived.

Answer 1

It has been the stoic philosophy, especially in the guise of the publications of Garve, Baumgarten, and Wolff:

Kant did not need Garve’s translation to remind him of the Stoic principle, which was still popular with eighteenth-century thinkers like Wolff and Baumgarten; and the other variants [of the categorical imperative] are hardly directed against Cicero. (Timmermann, J. (Ed.). (2009). Kant's' Groundwork of the Metaphysics of Morals': A Critical Guide. Cambridge University Press, p. xxviii)

This makes also clear that Kant did not want to argue against popular moral philosophy (i.e. its content - he was critical of its methods): he rather considered the categorical imperative to be the (implicit) basis of it.

Kant's own reference to "popular moral philosophy"

What popular moral philosophy meant for Kant is further elaborated by Timmermann at a later point in his text: it refers to Garve in particular (who recently had published both a translation of Cicero's De officiis and a book that could be seen as a comment to it) in at least one case, here in a comment to Ak. 4:409.20:

One is reminded of Cicero’s De officiis and Christian Garve’s Philosophische Anmerkungen und Abhandlungen, both equally eclectic and riddled with historical examples. It is difficult to believe that at least the present attack on contemporary popular moral philosophy was not inspired by Garve’s 1783 twin publications. (ibid:56)

The understanding that it is Garve in particular (and not Baumgarten and Wolff) is further supported by Allison:

As the title suggests, it [i.e. the second section] is concerned with the two approaches to moral philosophy in relation to which Kant largely framed his project in GMS: the universal practical philosophy, which was initially formulated by Wolff and further developed by Baumgarten and the latter's student Georg Friedrich Meier, and the eclectic “popular moral philosophy,“ which was associated with Christian Carve, as well as figures in the Berlin enlightenment. (Allison, H. E. (2011). Kant's Groundwork for the Metaphysics of Morals: a commentary. OUP Oxford, p. 37)

Answer 2

Following up on the answer of Philip Klöcking. In Critique of Pure Reason, Kant calls upon the writings of Alexander Baumgartner once, and those of Christian Wolff seven times.

See CPR at (http://www.gutenberg.org/files/4280/4280-h/4280-h.htm) [Meiklejohn trans., word searchable.]