It depends on the type of system in place and the circumstances between the people and their leader/s. War and violence are not the only options available to remove bad leaders, but sometimes such action is necessary.
In The Caucasian Chalk Circle, the Fat Prince staged a coup and murdered the governor. However, the coup was reversed, and the Grand Duke regained control. The story suggests that the governor was legitimately in authority, however, the prince, yearned for power leading to the violent takeover.
In a monarchy system of governance, authority and power are inherited. In a democracy, the people participate in selecting their leader. Public participation in republics reduces chances of war and violence because there is due process outlined in universally binding agreements such as the constitution. The agreement would generally provide the people with an opportunity to exercise their preferences by selecting another leader through a free and fair election.
In monarchies or dictatorial regimes, such opportunities are not available to the people forcing them to rise up in arms when faced with bad leaders. An example of such scenarios would be the French, American and English Revolutions.