Complex sentence: In 1277 AH/1860-61 AD, his father left his post, and father and son traveled throughout Europe into 1278 AH/1861-62, when his father was posted to the northern (Caspian) province of Gilan as governor.
Split into simpler sentences: In 1277 AH/1860-61 AD, his father left his post, and father and son traveled throughout Europe. In 1278 AH/1861-62, his father was posted to the northern (Caspian) province of Gilan as governor.