whether salafis/wahhabis are a majority in saudi arabia is disputed, with one estimate putting their number at only 22.9% of the native population (concentrated in najd). the wahhabi mission has been dominant in najd for two hundred years, but in most other parts of the country—hejaz, the eastern province, najran—it has dominated only since 1913-1925. most of the 15 to 20 million saudi citizens are sunni muslims, while the eastern regions are populated mostly by twelver shia, and there are zaydi shia in the southern regions. according to a number of sources, only a minority of saudis consider themselves wahhabis, although according to other sources, the wahhabi affiliation is up to 40%, making it a very dominant minority, at the very least using a native population of 17 million based on "2008-9 estimates". in addition, the next largest affiliation is with salafism, which encompasses all of the central principles of wahhabism, with a number of minor additional accepted principles differentiating the two.