Syria’s road from French colony (er, I mean “protectorate” or whatever) to the mess it is today was littered with coups d’état: three in 1949, one each in 1951, 1954, 1961, 1963, and 1966, and finally the 1970 Corrective Movement that brought Hafez al-Assad to power. I’m probably missing a couple somewhere along the way. Through it all, Syria transitioned from democracy to military dictatorship, to leftist military dictatorship, to union with Egypt, to disunion with Egypt, to Baʿathist military dictatorship, to Syrian Baʿathist military dictatorship, and at last to Assad family fiefdom.
In terms of regional significance, the 1966 coup is arguably more important than the others, because it was this coup that led to the splintering of the once pan-Arab Baʿath Party into its two regional branches, in Syria and Iraq. If you ever wondered (and of course you did), back in the days when Saddam Hussein was still with us, why Syria and Iraq were both governed by “the Baʿath Party” but never got along with one another, the 1966 Syrian coup was the reason why.