A turbulent camel-breeding confederation whose territory touched the Gulf around Kuwait and ran inland down Wadi al-Batin to the edge of Ibn Saud's districts near Zulfi. Perpetually at feud with the Rashidi emirs of Ha'il — a Mutayri killed Emir Abd al-Aziz ibn Rashid in 1908 — the Mutayr harried the outlying settlements of Qasim and the caravan traffic to the Gulf, and under Faisal al-Duwaish became the core of the Ikhwan.
Not an ending: the Mutayr Ikhwan under Faisal al-Duwaish rebelled against Ibn Saud and were broken at the Battle of Sabilla in March 1929, al-Duwaish surrendering in 1930; the tribe survives inside Saudi Arabia, Kuwait and Iraq.
Its 'The Muteir and the Barriyah' section names the tribe's dirah landmarks, its sections and its paramount shaikh Faisal al-Duwaish on the eve of the Ikhwan revolt that ends this record. Full text read on the Internet Archive.
The standard scholarly account of the Ikhwan revolt and of al-Duwaish's Mutayr specifically — the terminal event for this record. Existence verified on Open Library (/works/OL2632215W).