History of Hajj
Hajj started with Ibraheem (Peace be upon him) who left his legacy both in the Hanifiyah, the pristine religion of Islam and in Hajj.
The legacy of Ibraheem (A) was his millah, way, of true submission to Allah. He was the first one who used the word "Islam". He named anyone holding to the same faith as him a Muslim meaning the one that surrenders and submits to the will of the Creator, Allah. We read in Surat al-Hajj,
"And strive in His cause as you ought to strive, (with sincerity and under discipline). He has chosen you, and has imposed no difficulties on you in religion; it is the way of your father Abraham. It is He who has named you Muslims, both before and in this (Revelation); that the Messenger may be a witness for you, and you are witnesses for mankind! So establish regular Prayer, give regular Charity, and hold fast to Allah! He is your Protector, the best to protect and the Best to help!" (22:78)
His submission and total surrender to the Will of Allah is related to his establishment of Hajj. Even if Ibraheem (A) did not remain in Makkah to the end of his life, he laid the foundations of the Ka'bah in the middle of Makkah valley as well as the principles of Tawheed, genuine monotheism, in the heart of his son Ismaeel (A). The latter was also a prophet and a messenger of Allah, who kept the promise to preserve and guard Ka'bah as well as the Islamic faith. Later on, one of his descendents through Kedar - the second son of Ishmael as prophesied in Genesis 25:13 and a few other places - Muhammad (S), who was also a Hanif, rejected the idolatry and paganism brought to Makkah and called to the same faith as his forefathers Ibraheem (A) Ismaeel (A). He was chosen by Allah to be the last Messenger sent as Mercy to the world. He restored that legacy, Islam, and preserved the Ka'bah from the alien beliefs and practices. He reminded people of the religion of Ibraheem (S) and its tenets and called everyone to the religion of Ibraaheem (Peace be upon him).
The building of the Ka'bah was by Ibraaheem and his son Ismaeel (Peace be upon them). This house was named "Ka'bah" after its cubic shape. It is the center point for Muslims all over the world. When a Muslim wants to pray, he, or she, must face Qiblah - the direction towards Makkah. Hajj also cannot be performed except in Makkah and its vicinity. The al-Masjid al-Haraam, holy mosque, was the first mosque built in the world. It is today the most visited place on earth and that is why it is called al-Bayt al-'ateeq meaning the ancient house. One prayer in this mosque equals one hundred thousands prayers elsewhere as stated in a few authentic hadiths.