Complex sentence: Suppiliuma's grandson Hattusili III in the middle 1200s BC wrote of the time before Tudhaliya that the Kaska had "made Nenassa their frontier" and that their allies in Azzi-Hayasa had done the same to Samuha.
Split into simpler sentences: Suppiliuma's grandson Hattusili III in the mid- 13th century BC wrote of the time before Tudhaliya. He said that in those days the Kaska had "made Nenassa their frontier" and that their allies in Azzi-Hayasa had done the same to Samuha.