The Geneva Conventions and their Additional Protocols are at the core of international humanitarian law, the body of international law that regulates the conduct of armed conflict and seeks to limit its effects. The Geneva Conventions that were adopted before 1949 were concerned with combatants only, not with civilians. However, the events of World War II showed the disastrous consequences of the absence of a convention for the protection of civilians in wartime. The fourth Geneva Convention however, affords protection to civilians, including in occupied territory.
Common Article 3, first adopted in 1929, but significantly updated in 1949, is common to the four Geneva Conventions and establishes fundamental rules from which no derogation is permitted. In particular, it requires humane treatment for all persons in enemy hands, without any adverse distinction. It specifically prohibits murder, mutilation, torture, cruel, humiliating and degrading treatment, the taking of hostages and unfair trial.

The Geneva Conventions entered into force on 21 October 1950.

Ratification grew steadily through the decades: 74 States ratified the Conventions during the 1950s, 48 States did so during the 1960s, 20 States signed on during the 1970s, and another 20 States did so during the 1980s. Twenty-six countries ratified the Conventions in the early 1990s, largely in the aftermath of the break-up of the Soviet Union, Czechoslovakia and the former Yugoslavia.

Seven new ratifications since 2000 have brought the total number of States Party to 194, making the Geneva Conventions universally applicable.

A full text of the Geneva Convention can be found at the website of The University of Minnesota

From: International Committee of the Red Cross (ICRC).

International humanitarian law is a set of rules which seek, for humanitarian reasons, to limit the effects of armed conflict. It protects persons who are not or are no longer participating in the hostilities and restricts the means and methods of warfare. International humanitarian law is also known as the law of war or the law of armed conflict.

International humanitarian law is part of international law, which is the body of rules governing relations between States. International law is contained in agreements between States – treaties or conventions –, in customary rules, which consist of State practise considered by them as legally binding, and in general principles.

International humanitarian law applies to armed conflicts. It does not regulate whether a State may actually use force; this is governed by an important, but distinct, part of international law set out in the United Nations Charter.

A Brief History of Humanitarian Law.

From: Peace Pledge Union.

The Geneva conventions have their origins in the Battle of Solferino in 1859, of which the aftermath was witnessed by a Swiss citizen named Henry Dunant. He was horrified by the sight of thousands of wounded soldiers lying helpless and abandoned with no one to care for them. He suggested the setting up of voluntary relief societies who could be trained, during peacetime, to care for the wounded in time of war and called for an international agreement to be drawn up to protect the wounded, and those who looked after them, from further attack.

In 1863 Henri Dunant arranged an unofficial international conference at which it was agreed that each country should form a relief organisation capable of assisting the Army Medical Services in wartime; the origins of the modern International Red Cross.

In 1864 governments were invited to send representatives to a diplomatic conference. As a result 12 European nations signed a treaty stating that in future wars they would care for all sick and wounded military personnel, regardless of nationality. They would also recognise the neutrality of medical personnel, hospitals and ambulances identified by the emblem of a red cross on a white background. The treaty was called the Geneva Convention.

• Wikipedia
• International Committee of the Red Cross
• Geneva Convention Time-Line
• The Geneva Convention