 Mocked as "Arch-Sleepyhead of the Holy Roman Empire" () during his lifetime, he is today increasingly seen as an effective ruler.Born at the Tyrolean residence of Innsbruck in 1415, Frederick was the eldest son of the Inner Austrian duke Ernest the Iron, a member of the Leopoldian line of the Habsburg dynasty, and his second wife Cymburgis of Masovia.According to the 1379 Treaty of Neuberg, the Leopoldinian branch ruled over the duchies of Styria, Carinthia and Carniola, or what was referred to as Inner Austria.