Each case is different. Historical territories and ancient borders can play a role in modern situations, especially when dealing with border disputes, territorial claims, or understanding a country's historical background. However, they are not always the main factor in determining modern territorial sovereignty. Here are some factors to consider: 1. **International Law**: Modern territorial sovereignty is usually determined by international law, treaties, and agreements. The League of Nations, established in 1919, and the United Nations, established in 1945, were designed to promote cooperation between countries, peaceful resolution of disputes, and respect for territorial integrity. 2. **Protocols on State Boundaries and Borders**: Borders are usually established and determined through bilateral or multilateral agreements, treaties, or conventions. These agreements can cover issues such as border demarcation, s?ng use rights, and cross-border movement. 3. **Self-determination**: The right to self-determination is a principle of international law that allows people to determine their own political status and future. States have the right to define their own territory in accordance with their own interests and the wishes of their people. 4. **Historical claims**: Historical claims, such as ancient territory or cultural ties, can inform modern territorial sovereignty, but usually require support from other factors, such as internationally recognized borders, effective control, or the wishes of the local population. 5. **Diplomacy and negotiation**: Modern territorial sovereignty often resolves border disputes or territorial disagreements through diplomatic efforts, negotiation, and compromise. Historical examples show that ancient borders can affect modern sovereignty in complex ways: * **China's "Nine-Dash Line"**: China's claim to historical sovereignty over the South China Sea is based on the 13th-century Ming Dynasty maritime boundaries. However, this claim is controversial and contested by neighboring countries and international law. * **Israel-Palestine conflict**: Both Israel and the Palestinian Authority claim historical ties to the region, but modern border and sovereignty issues remain the focus of diplomatic efforts and negotiations by the international community. * **British-Argentine sobre Malvinas (Falkland Islands)**: Argentina claims sovereignty over the islands, citing historical ties and geographical proximity as its basis. However, Britain claims sovereignty over the islands based on its first occupation in the 18th century and the wishes of the local population. In conclusion, ancient territories and borders can influence modern sovereignty, but they are not the decisive factors. International law, border agreements, self-determination, diplomatic efforts and negotiations often play a more important role in shaping modern territorial sovereignty.