Complex sentence: In a written work of 169 BC, he advocated a systematic policy to populate frontier zones with migrants supported by the government who could simultaneously train as militia units while developing and cultivating remote regions which were under frequent attackt by nomadic forces.
Split into simpler sentences: In a written work of 169 BC, he advocated a systematic policy to populate and defend frontier zones. He proposed that civilian migrants supported by the government could simultaneously train as militia units while developing and cultivating remote regions which were under frequent attack by nomadic forces.