Although, you will note from that article that he was commissioned as a Lt. Col. 3-4 months after his enlistment as a private. It was not uncommon at the time for wealthy or upper class men to obtain a military commission as an officer with very little prior training. How it happened in his case:
OTOH, Edward VIII was the only man in history to go from Admiral of the Fleet to Third Mate on an American tramp. 
IIRC, Jimmy Stewart enlisted as a private and worked his way up to general.
Right you are: James Stewart - Wikipedia
For another real-life backward career move, T.E. Lawrence (“Lawrence of Arabia”) retired from the British Army as a full colonel, and shortly afterwards enlisted in the Royal Air Force as an aircraftman (under a false name).
Admiral Yi of Korea did it multiple times, thanks to being a kickass commander, but having powerful rivals constantly bringing him down.
Did you just make that up?
Would love to claim credit, but I heard it years ago.
Sam Houston enlisted as a Private for the War of 1812 and ended up as Commander In Chief of the Texas army during the Revolution, then served as President of the Republic of Texas. He was also Gov. of Texas and a US Senator and, except for the fact he seems to have been bat s crazy would have had a good chance of winning the US Presidency in 1856.
He actually ran for the Know Nothing nomination in 1856 but didn’t get it. He was on the right side of history when Texas seceded, however: Sam Houston - Wikipedia
Bumped.
Just learned that Nathanael Greene went from private in the Rhode Island militia to major general in the Continental Army. By the end of the American Revolution, he was one of Washington’s most capable and trusted generals: Nathanael Greene - Wikipedia
General Idi Amin Dada started as a cook in the Ugandan army and ended up President for Life…
One factoid I read about him mentioned that he was the first native African head of State that was not a British-educated graduate.
I think Hitler was a private in the World War I, and Supreme Leader in the 2nd.
He didn’t exactly get the latter job by rising through the ranks of the German Army, though.
As already mentioned upthread.
md2000’s suggestion of Idi Amin seems to be spot-on, though. He really does seem to have started at the lowest enlisted rank and worked his way up through promotions, then a commission, then more promotions to the commander of the entire armed forces. And all this before he seized political power in a military coup.
Actually, that piece isn’t accurate. The Joint Chiefs do hold the highest ranks available in the officer corps. Others also hold that rank. If you are talking about senior by duty position they are “outranked” by the Combatant Commanders. The Combatant Commanders work directly for the National Command Authority(NCA), which is the combination of the President and Secretary of Defense. POTUS and SECDEF both can issue legal orders to Combatant Commanders. The Joint Chiefs advise NCA. They legally do not have executive authority over the Combatant Commanders. They haven’t since 1953.
It’s an important point because there’s a pretty high profile name that went from enlisted to Combatant Command that hasn’t been mentioned yet. That is John Kelly, current Chief of Staff in the Trump administration. He first enlisted in 1970. In 2016 he retired after leading Southern Command.
I see you and raise - Basil I. His life was a soap opera.
Word back in the day is that this guy was the first Mustang to make full Commander. It was well deserved if true. I would have taken a bullet in a non-vital organ for the man. For his replacement, I’d keep my head down.
Papa George was the best boss I ever had. I raise one in his memory.
Fair winds and following seas, wherever you are, Sir.