The word pacifism was coined in 1901, though opposition to war is ancient
French peace campaigner Émile Arnaud invented the word pacifism, and fellow activists took it up when their tenth international peace congress met in Glasgow in 1901. The idea behind it is far older, from the Hindu, Buddhist and Jain principle of ahimsa to an ancient Chinese school that defended small states from invasion.
That school was the Mohists of China's Warring States period, who opposed aggressive war and used renowned defensive techniques to protect weaker states, hoping to convince lords that conquest cost too much. China's Seven Military Classics likewise treat war as a last resort. In the southern French Congo, the Lemba religion took its name from the words for peace, and ancient Greece offered Aristophanes' Lysistrata, a comic tale of Athenian women staging a sex strike to end the Peloponnesian War of 431 to 404 BCE.
Modern pacifism owes much to Leo Tolstoy's late writings, especially The Kingdom of God Is Within You. Mahatma Gandhi turned steadfast nonviolent resistance, which he called satyagraha, into a force in India's independence movement, inspiring Martin Luther King Jr., James Lawson, James Bevel and Thích Nhất Hạnh. Not every nonviolent campaigner was an absolute pacifist, though; the 1965 march from Selma to Montgomery called for armed protection.
The label covers a spectrum. Historians Peter Brock and Thomas Socknat describe the usual English sense as unconditional rejection of all warfare, and philosopher Jenny Teichman calls its main form anti-warism. Some ground it in moral principle, others in the pragmatic view that war costs too much. Absolute pacifists, as the BBC puts it, reject killing even in self-defence, while conditional pacifists, drawing on just war theory, may allow defence without favouring intervention.
History has tested these lines. When North and South went to war in America, a peace society and several former non-resisters sided with the Union, describing its fighting as a police action. In the 1960s some New Left pacifists supported wars of national liberation, arguing peaceful routes had failed. Others limit themselves to symbolic property damage, such as pouring red paint at recruiting offices or hammering on military aircraft.
Source: Pacifism