Complex sentence: Due to his devotion, he was elected the chief of the Jaipur Rajya Praja Mandal in 1938.While he was a chief, he negotiated truce between maharajas of Sikar and Jaipur.
Split into simpler sentences: Due to his devotion, he was elected the chief of the Jaipur Rajya Praja Mandal in 1938. While chief, he negotiated a truce between the maharajas of Sikar and Jaipur.