The Karen people are considered to be the largest of more than a dozen ethnic minority groups in Burma. During the second World War, Karen soldiers fought alongside the British army and Allied forces against the occupying Japanese but also against many ethnic Burmen nationalists, who favored independence from British colonial rule.
Karen and other ethnic minorities were promised autonomy after the war, a promise quickly forgotten once Burma became independent of colonial rule in 1948. Provisional agreements with ethnic minority groups were ignored by the new Burmen-dominated government. This prompted many of the ethnic groups fighting an insurgency for political autonomy, a conflict that has lead more than six decades of civil war; the longest running war in the world.