Complex sentence: Husni al-Za'im became the first military dictator of Syria in 1949, but in 1950, military officer Adib Shishakli gained power behind the scenes, and by 1953 had established another military dictatorship.
Split into simpler sentences: Husni al-Za'im became the first military dictator of Syria in 1949, but his rule proved short-lived. Not long afterwards, in 1950, Adib Shishakli, a military officer, gained power behind the scenes, and by 1953 he had established another military dictatorship.