Final answer:
Czechoslovakia and Yugoslavia split due to ethnic tensions, the collapse of communism, and the desire for independence. Czechoslovakia peacefully agreed to separate into two states, while Yugoslavia faced violent conflict.
Step-by-step explanation:
The split of Czechoslovakia and Yugoslavia can be attributed to various factors, including ethnic tensions, the collapse of communism, and the desire for independence. In the case of Czechoslovakia, the country peacefully agreed to separate into the Czech Republic and the Republic of Slovakia, as they organized around the concept of nation-states. On the other hand, Yugoslavia faced violent conflict due to the diverse ethnic groups within the country. After the death of leader Josip Broz Tito in 1980, ethnic tensions increased, leading to the breakup of Yugoslavia into several independent states.