There are many contested borders and not all nation states are universally recognised -> For instance, Taiwan is not recognised as a sovereign state by China
This can lead to both potential conflict and population movements
The Sykes-Picot Agreement of 1916 was a secret deal between France and Britain, to divide parts of the Middle East between themselves
This agreement continues to influence the borders of today's nation states, including Iraq
Causes for contested borders include:
One state wishing to take over another (Russia v Ukraine)
A wish to unite culturally and ethnically similar populations
-> Turkey, Iraq and Syria promised a separate state
A desire to obtain access to valuable resources
-> China is claiming the Eleven-dash line
Ukraine / Russia / Crimea:
Crimea was considered part of Russia for many centuries, but in 1954 it became part of the Ukraine
In 2014, the then pro-Russian Ukraine president was forced out, and Russia annexed Crimea
Crimea's population voted to re-join Russia, however, few countries recognise Russia's claim
They argue that all of Ukraine should have voted, not just Crimea
Crimea is a strategic area of the Black Sea with vast reserves of oil and gas