Southeastern Anatolia is a unique part of Turkey with a predominantly Kurdish population, which is very welcoming to the Western traveler. Apart from the Kurds, some areas, such as the region around Urfa, are inhabited by Arabs. The region is also known for its religious diversity, with of course the obligatory Sunni Muslims, Kurdish Alevites, and a large variety of Christian cults. There are also lots of historical cities one can visit, such as mysterious Şanlıurfa, basalt-walled Diyarbakır, and golden Mardin, where one has the opportunity to meet the last Syrian and Armenian Christians and visit their churches and monasteries.
There's also some bad news. Like in Eastern Turkey, from 2015 onwards, the region cannot be considered to be safe for travel anymore. The security situation is unpredictable and there is a significant threat of terrorism and kidnapping. We can only hope that it will turn for the better in the near future.