Somaliland was first inhabited around 10,000 years ago during the Neolithic age. The ancient shepherds raised cows and other livestock and it has the most vibrant rock art paintings in Africa. Throughout the Middle Ages, Arab immigrants arrived in Somaliland, including the Muslim sheikhs Ishaaq bin Ahmed, who founded the Isaaq clan, and Abdirahman bin Isma'il al-Jabarti who founded the Darod clan, who both travelled from Arabia to Somaliland and married into the local Dir clan, although I.M. Lewis states that those are legendary stories. Also during the Middle Ages, Somali empires dominated the regional trade, including the Sultanate of Ifat and the Adal Sultanate.