Trial by ordeal in the context of "Manorial court"

Ranavalona I (born Rabodonandrianampoinimerina; 1778–16 August 1861), also known as Ramavo or Ranavalo-Manjaka I or Ranavalona reniny, was the sovereign of the Kingdom of Madagascar from 1828 to 1861. After positioning herself as queen following the death of her young husband Radama I, she pursued a policy of isolationism and self-sufficiency. She sought reduced economic and political ties with European powers and took vigorous measures to eradicate the small but growing Malagasy Christian movement initiated under Radama I by members of the London Missionary Society.

Ranavalona made heavy use of the traditional practice of fanompoana (forced labor as tax payment) to complete public works projects and develop an army. She had a standing army of between 20,000 and 30,000 Merina soldiers, whom she deployed to pacify outlying regions of the island and further expand the realm. The combination of regular warfare, slavery, disease, difficult forced labor and the practice of tangena (a harsh trial by ordeal using a poisonous nut from the Cerbera manghas tree) resulted in a high mortality rate among both soldiers and civilians during her 33-year reign, reducing Madagascar's population from 5 million in 1833 to 2.5 million in 1839.

Cerbera odollam is a tree species in the family Apocynaceae commonly known as the suicide tree or pong-pong. It bears a fruit known as othalanga whose seeds yield a potent poison called cerberin. It has historically been used in trials by ordeal, especially in Madagascar, where it has caused thousands of deaths annually, and continues to be used for suicide, particularly in Kerala, India. It can cause fatal heart arrhythmias with just one kernel and is responsible for numerous poisonings due to its easily masked taste and limited testing.

It is native to South and Southeast Asia, Pacific Islands, and Queensland, Australia, growing preferentially along sandy coasts, riverbanks, and by mangrove swamps. It is also grown in tropical areas such as Hawaii as an ornamental. It is a 10–12 meter tall plant with glossy leaves, white-yellow flowers, and poisonous seeds encased in a red-ripening fruit that resembles oleander and produces a milky latex. Its seeds are used as biopesticides, insect repellents, and rat poisons due to their toxicity and have also been studied as a non-edible, sustainable feedstock for biodiesel production on non-arable land.

The tangena ordeal was a form of trial by ordeal practiced in Madagascar to determine the guilt or innocence of an accused party. The trial utilized seeds of the tree species Cerbera manghas (family Apocynaceae), which produces seeds that contain highly toxic cardiac glycosides including cerberin and tanghinin.

The tradition of the tangena ordeal, dates to at least the 16th century in Imerina. It has been estimated that the poison may have been responsible for the deaths of as much as 2% of the population of the central province of Madagascar each year on average. Mortality peaked during the reign of Queen Ranavalona I (1828–1861), when the tangena ordeal was used extensively.