Datu Unsay, officially the Municipality of Datu Unsay, is a municipality in the province of Maguindanao del Sur, Philippines. According to the 2…Datu Unsay, officially the Municipality of Datu Unsay, is a municipality in the province of Maguindanao del Sur, Philippines. According to the 2020 census, it has a population of 12,890 people, making it the least populated municipality in the province.