Phnom penh: Cambodia has requested French assistance, including access to historical boundary documents and colonial-era maps, in hopes of resolving its ongoing border dispute with Thailand. This month, Cambodian Prime Minister Hun Manet wrote to French President Emmanuel Macron, stating that it would also welcome expertise and advisory support from the former colonial power. According to Deutsche Welle, Cambodia's Foreign Ministry expressed confidence that France's continued involvement would contribute to a peaceful and prosperous resolution, benefiting both Cambodian and Thai peoples. France ruled Cambodia as a protectorate from 1863 until independence in 1953. The 817-kilometer (507-mile) border between Cambodia and present-day Thailand was first mapped by French officials in 1907, based on the "watershed" principle that separates the basins of the Mekong and the Tonle Sap rivers. With France's withdrawal from the region, the demarcation line became a contentious issue, particularly around the 11th-cent ury temple of Preah Vihear, a significant nationalist symbol for both nations. While Thailand contends the temple lies north of the watershed line, Cambodia relies on maps placing the site within its territory. The International Court of Justice ruled in 1962 and again in 2013, affirming Cambodia's sovereignty over the temple. Tensions escalated again last year, leading to open conflict in July and December, resulting in 149 casualties, mostly civilians, and the displacement of hundreds of thousands, with approximately 800,000 Cambodian migrants returning from Thailand. Hun Manet's appeal to France has also raised broader questions about the lasting impact of colonial-era boundaries on contemporary Southeast Asian conflicts. Bernard Keo, assistant professor of International History and Politics at the Geneva Graduate Institute, commented to DW that colonialism is the foundational issue contributing to ongoing regional disputes, including the Thai-Cambodia border war.