The majority if not everybody in this forum has no idea about the history of Saudi Arabia, not at all. Not just this forum but in fact the entire world, unless you dig deep and cover old files and pictures of new articles in black and white and books long forgotten that it even existed, you will not find the true history of Saudi Arabia at all. Not even Saudis themselves are taught their own history subjectively.
When King Abdulaziz the founder of the third incarnation of the Saudi state declared the formation of the state, he wanted to follow the British experience to the letter. This included the nation to be a Secular state. This prompted a group of fighters known as the "Ikhwan" (Not to be confused with the Muslim Brotherhood, even though both of them are called Brotherhood) to revolt against King Abdulaziz because they wanted Sharia rulings. Their revolt failed and the state was established secular, part of the push to the future drive by King Abdulaziz. King Saud followed King Abdulaziz in this path after his death, however the MB infiltrated Saudi religious establishment (Which was US supported due to it being in opposition of Gamal Abdulnasser who was a Soviet ally) and with the help of King Faisal (The widely celebrated King of KSA, haha yeah right, if only people knew), dethroned King Saud for which he escaped to Egypt (Citing governmental corruption as the cause, essentially a religious coup).
King Faisal immediately invited the heavily prosecuted MB into the Kingdom, for which they gained a prominent position in the country and celebrated as religious heroes, and they started a social engineering project called (Al-Sahwah) for which we see the result of today.
Saudi Arabia in its establishment was a secular nation, King Saud was on the project of opening an elected parliament but all of that did not come to pass, and while US has its share of the blame for this, I blame the MB for enabling it, and ruining life in KSA for decades.