Contrary to what most Muslims believe, the name “Allah” had its roots in the ancient Aramaic language, not Arabic.
In Aramaic, the words Elaha and Eloyhim (and other variations such as Elah, Eloah and Alah) were used to refer to The Almighty.
Once utilized and arabized by Pagan Arabs in the 5th century BC, Allah became a common term used to describe the most powerful of all deities. Even Arab Christians of the following era referred to God as Allah. It became the generic word for “God” in the Arabic language.
The Pagan Arab’s Allah was an idol, a statue representation of a moon-god who resided inside the Kaabah and was continually worshiped for many years. He had three daughters; Al-Lat, Al-Uzza and Al-Manat.
In their hierarchical placement of Gods, the title Allah was given to any idol which was most popularly worshiped at the time. This belief would continue on until the birth of Islam in the 6th Century.
The Muslims fought to conquer Mecca (and the Kaabah) as Prophet Muhammad PBUH ordered the destruction of all idols and deities inside the Kaabah. Soon, the Pagan’s Allah was replaced by the Muslim’s Allah.
To prove how generic the term Allah was; the father of Prophet Muhammad was named Abdullah (Slave of Allah). His father died before Muhammad was born and even before the coming of Islam. So, which Allah was his father a slave to?
The First Generation of Muslims (before the conquest of Mekah) pledged their allegiance to Allah (as evident in the Shahada) even before they reinstated the “new” Allah. As Allah replaced “Allah”, the once revered idol has now been transformed into a conceptual, omnipotent, omniscient, omnibenevolent and omnipresent God which one can neither see nor touch. All one has to do is believe.
Even today, Allah is continually used by Arabs (mainly Muslims and Christians) to denote their own choice of god.