Although both speak the same language and believe the Christianity, the majority Hutus were mainly farmers, and the minority Tutsis were mainly herders. Since herders tend to make more money, the minority Tutsis became the local elite and started ruling a monarchy.
For the Hutu, this rules by Tutsi was a symbol of colonial era under Belgium, and this political system continued even after Rwanda became independent from Belgium in 1962.
Under this frustration, the majority Hutu attacked the minority Tutsi and overthrew the government, which led the Tutsi to flee to neighboring countries, such as Uganda.
Although the Hutu government tried to make a power-sharing agreement with the Tutsi, a Tutsi rebel group, the Rwandan Patriotic Front (RPF)led by Paul Kagame, took back the political power in Rwanda, which made the Hutu flee to the Democratic Republic of the Congo.
Moreover, since the influence of the Hutu increased in the refugee camp in the Democratic Republic of the Congo, the Tutsi invaded the Democratic Republic of the Congo to clear the threat in 1996.
After Paul Kagame was elected as Rwanda's new president in 2000, he conducted a peace deal with the Democratic Republic of the Congo(DRC) to make sure Rwanda to withdraw the troops from DRC and DRC to help disarm the Hutu. Multi-party parliamentary elections and new policy makings were also conducted with the aim to increase diversity
Paul Kagame revised a constitution to allow him to serve a third term in 2016 and won the election in 2017.