In 1930 Augustinčić created his first equestrian sculpture for the monument in Niš,[3] after his design won the competition out of the 23 works submitted, with prominent Yugoslav sculptors Risto Stijović and Sreten Stojanović coming in second and third.

[4] In the late 1930s he also created a couple of monuments to King Alexander in Sombor and Skopje (which were later destroyed in World War II), as well as several sculptures of Croatian politician Stjepan Radić.

His most important sculpture in this period is The Carrying of the Wounded (Croatian: Nošenje ranjenika), which evolved from a sketch made in 1944 and which he used as a recurring motif in a number of monuments he created in the following three decades,[1] one of which can be seen in front of the Faculty of Medicine in Zagreb.

Augustinčić, together with the Serbian painter Đorđe Andrejević-Kun, also designed all of the Yugoslav orders and decorations, and he also created the coat of arms of the Socialist Republic of Croatia (with Vanja Radauš).

[10] To provide feedback and instruction for the Harar monument, the renowned Ethiopian artist Afewerk Tekle went to Zagreb where he exchanged ideas with Augustinčić.

[2] His last great work was the memorial dedicated to the 1573 Peasants' Revolt and its leader Matija Gubec, which was erected near Oršić Castle in Gornja Stubica in 1973.