Ranwadi traces its origins to 1902, when a local man named Willie Tabimamkan returned from working on a Queensland sugar plantation with a "burning desire" to tell people about Jesus. Tabimamkan wrote to Australia asking for help, and in response, a missionary named John Thompson arrived in 1903. Malaria forced Thompson to leave later that year, but his arrival marked the beginning of the work of the Churches of Christ Overseas Mission Board in the area, which continues to this day. The next white missionary was Frank Filmer, who stayed at Ranwadi from 1908 until 1912.