Complex sentence: With the growth of the threat from Philistine incursions, the Israelite tribes decided to form a strong centralised monarchy to meet the challenge, and the Tribe of Ephraim joined the new kingdom with Saul as the first king.
Split into simpler sentences: With the growth of the threat from Philistine incursions, the Israelite tribes decided to form a strong centralised monarchy to meet the challenge. The Tribe of Ephraim joined the new kingdom with Saul as the first king.