Complex sentence: Traditionally, titles of the royal wives depended both on their birth titles and royal favour, with only the princesses who are of high birth (Chao Fa, Phra Ong Chao, Mom Chao Ying) taking up titles higher than Chao Chom.
Split into simpler sentences: Traditionally, titles of the royal wives depended both on their birth titles and royal favour. Only the princesses who are of high birth (Chao Fa, Phra Ong Chao, Mom Chao Ying) would be able to take up titles higher than Chao Chom.