Mass suicide sometimes occurs in religious or cultic settings. Suicide missions, suicide bombers, and kamikazes are military or paramilitary forms of mass suicide. Defeated groups may resort to mass suicide rather than capture. Suicide pacts are a form of mass suicide unconnected to cults or war that are sometimes planned or carried out by small groups of frustrated people, typically lovers. Mass suicides have been used as a form of political protest.
During the late 2nd century BC, the Teutons are recorded as marching south through Gaul along with their neighbors, the Cimbri, and attacking Roman Italy. After several victories for the invading armies, the Cimbri and Teutones were then defeated by Gaius Marius in 102 BC at the Battle of Aquae Sextiae (near present-day Aix-en-Provence). Their King, Teutobod, was taken in irons. The captured women committed mass suicide, which passed into Roman legends of Germanic heroism: By the conditions of the surrender three hundred of their married women were to be handed over to the Romans. When the Teuton matrons heard of this stipulation they first begged the consul that they might be set apart to minister in the temples of Ceres and Venus; and then when they failed to obtain their request and were removed by the lictors, they slew their little children and next morning were all found dead in each other's arms having strangled themselves in the night.
The 960 members of the Jewish community at Masada, who collectively committed suicide in the first century A.D., rather than be conquered and enslaved by the Romans. Each man killed his wife and children, then the men drew lots and killed each other until the last man killed himself.
The occasional practice of mass suicide known as Jauhar was carried out in medieval times by Rajput communities, when the fall of a besieged city was certain in order to avoid capture, dishonour and forced conversion. The best known cases of Jauhar are the three occurrences at the fort of Chittaur in Rajasthan, in 1303, in 1535, and 1568.
In April and May 1945 about 900 residents of Demmin, Germany, committed mass suicide in fear of the advancing Red Army.
Japan is known for its centuries of suicide tradition, from seppuku ceremonial self-disemboweling to kamikaze warriors flying their aircraft into American warships during World War II. During that same war on the island of Saipan hundreds of trapped Japanese committed mass suicide rather than surrender to the invading American forces. 
The Jonestown suicides in Guyana, where 913 people died in 1978 under the direction of Jim Jones, an evangelist preacher and head of the Peoples Temple. Of the 914 dead, 276 were children and over 100 of the adults were murdered.
The Heaven's Gate mass suicide occurred in a hilltop mansion near San Diego, California, in 1997. They believed an alien spaceship was following in the tail of the Comet Hale-Bopp and that killing themselves was necessary to reach it. The victims were self-drugged and then suffocated by other members in a series of suicides over a period of three days. Thirty-nine died, from a wide range of backgrounds.