While there are nearly 200 nation-states today, less than one-third of these existed as such forty years ago. Identify whether or not these are key events of the last century that led to the establishment of many of today's nation-states.

Key events that led to the formation of lot of states were the fall of communism, change of politics and economic systems, rising nationalism in some parts of the world, conflicts between different ethnic and religious groups, abandoning the colonial policies.

Explanation:

In the last forty years, the number of countries in the world has increased by approximately 50%. The majority of these new countries formed in Europe, Asia, and Oceania. The reasons for such rapid formation of such high number of new countries were:

fall of communism change of politics and economic systems abandoning the colonial policies ethnic and religious conflicts rising nationalism

The majority of the new countries in Europe and Asia were a result of the fall of the communism, so lot of countries formed on what was once the Soviet Union and Yugoslavia, as well some countries that split into two, like Czechoslovakia.

The abandoning of the colonial policies gave birth to the majority of the countries in Oceania, though that process only influenced half of those territories. Ethnic and religious problems, mainly in Africa resulted in splitting of countries, thus formation of new ones, such as Sudan and South Sudan.