Treaties in International Law



9 Questions

What is a treaty?

What is the 1969 Vienna Convention on the Law of Treaties?

What is the difference between bilateral and multilateral treaties?

What are reservations in the context of treaties?

What are the three ways an existing treaty can be amended?

What is the difference between self-executing and non-self-executing treaties?

What is the purpose of treaties with Indigenous peoples in Canada?

What is Terra nullius?

What is the difference between how Indigenous peoples and non-Indigenous peoples perceive treaties?


Overview of Treaties in International Law

  • A treaty is a formal, legally binding written agreement between actors in international law, usually made by and between sovereign states, but can include international organizations, individuals, business entities, and other legal persons.

  • The 1969 Vienna Convention on the Law of Treaties codified the guidelines and rules for creating, amending, interpreting, and terminating treaties and for resolving disputes and alleged breaches.

  • Treaties serve as primary sources of international law and have codified or established most international legal principles since the early 20th century.

  • A treaty typically begins with a preamble describing the "High Contracting Parties" and their shared objectives in executing the treaty, as well as summarizing any underlying events.

  • Bilateral treaties are concluded between two states or entities, while multilateral treaties are concluded among several countries.

  • The United Nations has extensive power to convene states to enact large-scale multilateral treaties and has experience doing so.

  • Reservations are unilateral statements purporting to exclude or modify the legal obligation and its effects on the reserving state.

  • There are three ways an existing treaty can be amended: a formal amendment, informal amendment, and protocol.

  • Treaties may be seen as "self-executing", or non-self-executing and require "implementing legislation".

  • The language of treaties must be interpreted when the wording does not seem clear, or it is not immediately apparent how it should be applied in a perhaps unforeseen circumstance.

  • While the Vienna Convention provides a general dispute resolution mechanism, many treaties specify a process outside the convention for arbitrating disputes and alleged breaches.

  • Treaties are not necessarily permanently binding upon the signatory parties, and withdrawal is possible.Overview of International Treaties and their Validity

  • Some treaties allow for withdrawal by following certain procedures of notification, while others expressly forbid it.

  • A material breach of treaty obligations may result in the temporary suspension or permanent termination of the treaty.

  • Treaties may include provisions for self-termination or may be intended to be only temporarily binding.

  • A party may claim that a treaty should be terminated due to a fundamental change in circumstances.

  • Cartels were a special kind of treaty in the 17th to 19th centuries that regulated specific activities of common interest among contracting states that otherwise remained rivals in other areas.

  • An otherwise valid treaty may be rejected as a binding international agreement due to being forced upon a party or being in violation of a peremptory norm.

  • A party's consent to a treaty is invalid if it had been given by an agent or body without power to do so under that state's domestic laws.

  • Consent may also be invalidated if it was induced by misunderstanding, fraud, corruption, or coercion.

  • A treaty is null and void if it is in violation of a peremptory norm.

  • In Australia, treaties are considered a source of law but may require an act of parliament to be passed depending on their nature.

  • In Brazil, treaties must be approved by Congress and incorporated into domestic law by means of a presidential decree.

  • The United States distinguishes between "treaties", "executive agreements", and "congressional-executive agreements", which are subject to different political and legal requirements and implications.

  • Treaties have played an important role in European colonization and have been used to legitimize sovereignty and maintain autonomy for indigenous peoples in some cases.Treaties with Indigenous Peoples: A Look at Australia, the United States, and Canada

  • Terra nullius was the doctrine adopted by Europeans to claim land ownership in Australia, despite no treaty being entered into with the Indigenous peoples, except in South Australia.

  • The Victorian First Peoples' Assembly was established in Australia in 2019 to work out the rules for individual treaties to be negotiated between the government and Indigenous peoples.

  • Before 1871, the government of the United States regularly entered into treaties with Native Americans, but the Indian Appropriations Act of 1871 effectively ended this practice.

  • In Canada, historic treaties fall into three categories: commercial, alliance, and territorial, with territorial treaties being signed between 1760 and 1923 to dictate land rights.

  • The Indigenous understanding of treaties is based on traditional culture and values, which emphasizes maintaining healthy and equitable relationships with other nations and the environment.

  • Gdoo-naaganinaa, a historic treaty between the Nishnaabeg nation and the Haudenosaunee Confederacy, is an example of how First Nations approach treaties, as a living and equitable agreement that must be upheld continually and renewed over time.

  • European settlers in Canada had a different perception of treaties, viewing them as legal contracts over which future Canadian law would rely on.

  • Canada recognizes 25 Modern Treaties that represent the relationships between 97 Indigenous groups, including over 89,000 people.

  • Modern treaties in Canada have been instrumental in strengthening Indigenous sovereignty and self-determination.

  • Treaties today provide Indigenous peoples with a means of asserting their rights, protecting their lands and resources, and achieving self-determination.

  • Treaties also serve as a reminder of past injustices and the need for reconciliation.

  • The perception of treaties varies between Indigenous peoples and non-Indigenous peoples, with Indigenous peoples viewing them as living and equitable agreements and non-Indigenous peoples viewing them as legal contracts.


Test your knowledge on treaties in international law with this informative quiz. Learn about the guidelines and rules for creating, amending, interpreting, and terminating treaties, as well as the different types and parties involved. Discover the importance of treaties in European colonization and their role in maintaining autonomy for indigenous peoples. See how treaties are perceived differently by different groups and countries. Take the quiz and become an expert on treaties in international law!

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