The Necromancer Lands, or, as they are called in their own tongue the "Khalipha al-Khalid", are inhabited by a mixture of peoples of primarily south Indian and Arabic descent. Before the rise of the Necromancer Al-Khalid, they worshiped many gods, both Hindu and Semitic. The nation, at the southern end of the Tirnakaur peninsula was once known as the kingdom of "Dar al Salaam", and was wisely ruled by it's Malik (King) and his viziers. They were a peaceful nation without any territorial ambitions. They were a land of many gods and unique sorceries. Al-Khalid left this land to go study at the vaunted academies of High Wizardry in Frodia and expand his knowledge, since, as a prodigy, he had mastered everything his lands had to teach before he was 30 years of age.
He studied for another pair of decades in Frodia before his true nature was ferreted out by the council of sorcerous masters there, by then it was too late. He had developed a coterie of followers and made good his escape to his homeland, where, as the heir to a noble house with wealth and influence at the Malik's court, and being probably the most powerful wizard ever to live; he quickly managed to take control of the government and launched a holy war against the rest of the world just over 600 years ago.
The Necromancer Lands in many ways became a dark mirror of Frodia after the Necromancer war, it's state religion still incorporates the worship of many deities, but in an altered fashion and the more evil practices are open and common. Kali and the Thuggee cult have risen in popularity. But the Necromancer Al-Khalid himself is considered the undying prophet that taught his people the way of immortality through Undeath. Lichdom is, of course the most popular option for the powerful among the ruling caste of Wizards and Priests. Vampirism is a popular option among some of the noble houses. The lower classes are happy to serve as Zombie or Skeletons in the ranks of the Caliph's armies. There are no cemeteries in the Necromancer Lands, they are the lands where everyone serves on after death.
After the war was obviously going to be lost against the coalition of forces from the rest of the known world, the Necromancer had the foresight to begin construction of an impressive and impregnable line of fortresses covering the mountain passes from Tirnakaur into his homeland, it's impressive what you can get done with a tireless workforce of Undead and a cadre of powerful Sorcerers at your command.
When Al-Khalid was finally defeated in an open field battle on the coastal plain of western Tirnakaur by a coalition army consisting of Garnian, Frodian, Tirnakaurian, Ming, Khazaraki, Mistlander, Steppe Barbarian and, in a surprise last minute appearance, Sidhe forces; the line of fortresses didn't seem necessary to breach; so they stand to this day. Manned by Human and Undead troops, occasionally sending probes out into the Tirnakaur wilderness, but the nation largely is a hermit kingdom now.
Al-Khalid was never confirmed dead. He may have transported to another plane as a last ditch escape attempt and he may come back to assume his throne at any time.