Complex sentence: The Liberals were strong enough to win the war in two months, but an inefficient government and the dispersion of the Carlist forces gave Carlos time to consolidate his forces and hold out for almost seven years in the northern and eastern provinces.
Split into simpler sentences: The Liberals were strong enough to win the war in two months. But, an inefficient government and the dispersion of the Carlist forces gave Carlos time to consolidate his forces and hold out for almost seven years in the northern and eastern provinces.