A war of independence is a conflict occurring over a territory that has declared independence. Once the state that previously held the territory sends in military forces to assert its sovereignty or the native population clashes with the former occupier, a separatist rebellion has begun. If a new state is successfully established, the conflict is subsequently known as a war of independence.

Use of the term largely originates from the American War of Independence but prior conflicts sometimes got the name retroactively—such as the Dutch War of Independence, originally known as the "Eighty Years' War" and still often called by that name in the Netherlands themselves.

War of independence were followed by the decolonization period Wars of national liberation.

Examples of war of independence include: