The Quraish people and those who embraced their religion, used to stay at Muzdalifa and used to call themselves Al-Hums, while the rest of the Arabs used to stay at ʿArafat. When Islam came, Allah ordered His Prophet to go to ʿArafat and stay at it, and then pass on from there, and that is what is meant by the Statement of Allah:--"Then depart from the place whence all the people depart......" (2.199)
عَنْ عَائِشَةَ ؓ كَانَتْ قُرَيْشٌ وَمَنْ دَانَ دِينَهَا يَقِفُونَ بِالْمُزْدَلِفَةِ وَكَانُوا يُسَمَّوْنَ الْحُمْسَ وَكَانَ سَائِرُ الْعَرَبِ يَقِفُونَ بِعَرَفَاتٍ فَلَمَّا جَاءَ الإِسْلاَمُ أَمَرَ اللَّهُ نَبِيَّهُ ﷺ أَنْ يَأْتِيَ عَرَفَاتٍ ثُمَّ يَقِفَ بِهَا ثُمَّ يُفِيضَ مِنْهَا فَذَلِكَ قَوْلُهُ تَعَالَى {ثُمَّ أَفِيضُوا مِنْ حَيْثُ أَفَاضَ النَّاسُ}