The original Sheik was a legend in his own right. The Iron Sheik was a whole different animal. I remember seeing a documentary about him several years ago. It talked about his tough upbringing in Iran, learning to wrestle there and I believe he was a body guard for the last Shah (King) of Iran. I think he began looking for a better and safer life, wanting to return to his wrestling roots, so he moved to the US. He coached some US Olympic squads before Verne Gagne found him and trained him as a professional wrestler. He was in the same class as Ric Flair, and he would later teach Ricky Steamboat among others. He worked for a bunch of different promotions in the late 70s and early 80s before he was selected to be the interim champion that would drop the belt to Hulk Hogan and start Hulkamania. The guy that had the belt before Sheik was Bob Backlund, I want to say Backlund had beef with Hogan and didn't want to be the one that lost to him.
The cocaine scandal with Hacksaw Jim Duggan was huge, one of the first big kayfabe breaking moments in the coming decade that ended up confirming that pro wrestling was staged. It ended up in his release from the WWF, although he'd find his way back a few times after. He did have a high profile feud with Hogan again when he teamed up with Srgt. Slaughter as Slaughter played a turncoat during the Iraqi war. He cut some great promos during this time, although his promos were always great. He was mostly retired from wrestling in the late 90s, but he would go on to win a Gimmick Battle Royal at Wrestlemania 18 in 2001 and would wrestle sporadically until he was 67.
One of his daughters was tragically murdered by a boyfriend in 2003, which really left a mark on him for a long time. His drug use increased heavily, causing his wife to leave him for a bit as he went in and out of rehab before finally getting clean supposedly. If I remember from the documentary she was training to be a wrestler and follow in her father's footsteps. Sheik, of course, was a legend outside of the squared circle too. He achieved another cult following on Howard Stern interviews where he bashed Hulk Hogan and other wrestlers, and he'd later have his infamous Twitter account run by his managers where he would do more of the same and weigh in on pop culture. While he played a heel most of his life, the documentary painted him as a strong family man that loved the USA. We also have the Iron Sheik to thank for Dwayne "The Rock" Johnson's famous catchphrase "jabronni." Apparently that was a term he heard from Sheik use in the lockerrooms all the time back in the day, calling him "Uncle Sheiky" and he adopted it as his own.