 Pottery dated at around 2500 BCE showing similarities with later Igbo work was found at Nsukka , along with pottery and tools at nearby Ibagwa ; the traditions of the Umueri clan have as their source the Anambra valley . In the 1970s the Owerri , Okigwe , Orlu , Awgu , Udi and Awka divisions were determined to constitute " an Igbo heartland " from the linguistic and cultural evidence . 
