I have loved the people of the tribe of Bani tamim ever since I heard, three things, Allah's Apostle said about them. I heard him saying,

These people (of the tribe of Bani tamim) would stand firm against Ad-dajjal."

When the Sadaqat (gifts of charity) from that tribe came, Allah's Apostle said,
"These are the Sadaqat (i.e. charitable gifts) of our folk."

'Aisha had a slave-girl from that tribe, and the Prophet said to 'Aisha, "Manumit her as she is a descendant of Ishmael (the Prophet)."

(Sahih Al Bukhari. Book #46, Hadith #719) (Bukhari Book #59, Hadith #652)(Sahih Al-Muslim. Book #031, Hadith #6133,6134)

Narrated Abu Huraira: I have not ceased to like Banu tamim ever since I heard of three qualities attributed to them by Allah's Apostle (He said): They, out of all my followers, will be the strongest opponent of Ad-dajjal; 'Aisha had a slave-girl from them, and the Prophet told her to manumit her as she was from the descendants of (the Prophet) Ishmael; and, when their Zakat was brought, the Prophet said, "This is the Zakat of my people."

(Book #59, Hadith #652)

Abu Huraira reported: Since I heard three things from Allah's Messenger (may peace be upon him) my love for Banu tamim is never on the decline (and these things are): I heard Allah's Messenger (may peace be upon him) as saying about them that they would put up stout resistance against Dajjal amongst my Umma. And he (the narrator) said: (When) the consignment of Zakat was brought to him, Allah's Messenger (may peace be upon him) said: This is the charity of our people, and there was one slave-girl in the house of 'A'isha and she was from the tribe of Banu tamim; thereupon Allah's Messenger (may peace be upon him) said: Set her free, for she is from the offspring of Isma'il. The other hadith has been transmitted on the authority of Abu Huraira with a slight variation of wording.

(Sahih Al-Muslim. Book #031, Hadith #6133)

Abu Huraira reported: There are some distinguishing features of Banu tamim which I heard from Allah's Messenger (may peace be upon him) and my love for them is never on the decline after that and the words are: They are the bravest amongst people in the battlefield and there is no mention of (the word)" Dajjal".

(Sahih Al-Muslim. Book #031, Hadith #6134)

Ibn Hajr al-Asqalaanee said, "this hadeeth also contains a clear mention of the excellence and superiority of Bani Tameem." [Fath 5/217]

Banu Tamim are the majority of people of the so-called Najd (Saudi Arabia). To label Najd as that area of Saudi Arabia would be in contradiction of the many hadeeth relating to Bani Tameem especially those in which they fight the Dajjal, who comes from the Najd that is to the East.