Najd (Arabic: نَجْدٌ,), or the Nejd, forms the geographic center of Saudi Arabia, accounting for about a third of the country›s modern population and, since the Emirate of Diriyah, acting as the base for all unification campaigns by the House of Saud to bring Arabia under a single polity and under the Salafi jurisprudence.
Historic Najd was divided into three modern administrative regions still in use today. The Riyadh region, featuring Wadi Hanifa and the Tuwaiq escarpment, which houses easterly Yamama with the Saudi capital, Riyadh since 1824.
