Complex sentence: El Sharih Yahdhib took the reins during a period that witnessed the shrinking influence of the Kingdom of Saba' and a decline of power which led to the independence and emergence of the Kingdoms of Ḥimyar and Hadhramaut.
Split into simpler sentences: El Sharih Yahdhib reigned during a period which witnessed the shrinking influence and a decline of power of the Kingdom of Saba'. This led to the emergence and independence of the Kingdoms of Ḥimyar and Hadhramaut.