The law of the sea developed from the struggle between coastal states, who sought to expand their control over marine areas adjacent to their coastlines. By the end of the 18th century, it was understood that states had sovereignty over their territorial sea. The maximum breadth of the territorial sea was generally considered to be three miles - the distance that a shore-based cannon could reach and that a coastal state could therefore control.
After the Second World War, the international community requested that the United Nations International law Commission consider codifying the existing laws relating to the oceans. The commission began working towards this in 1949 and prepared four draft conventions, which were adopted at the first UN Conference on the Law of the Sea:
The First United Nations Conference on the Law of the Sea (UNCLOS I) from February 24 until April 29, 1958. UNCLOS I adopted the four conventions, which are commonly known as the 1958 Geneva Conventions:
- The Convention on the Territorial Sea and Contiguous Zone;
- The Convention on the High Seas;
- The Convention on Fishing and Conservation of the Living Resources of the
- High Seas; and
- The Convention on the Continental Shelf.
While considered to be a step forward, the conventions did not establish a maximum breadth of the territorial sea.
The Second United Nations Conference on the Law of the Sea (UNCLOS II) from March 17 until April 26, 1960. UNCLOS II did not result in any international agreements. The conference once again failed to fix a uniform breadth for the territorial or establish consensus on sovereign fishing rights.
The Third United Nations Conference on the Law of the Sea (UNCLOS III) from 1973 to 1982. UNCLOS III addressed the issues bought up at the previous conferences. Over 160 nations participated in the 9-year convention, which finally came into force on November 14, 1994, 21 years after the first meeting of UNCLOS III and one year after ratification by the sixtieth state. The first sixty ratifications were almost all developing states.
A major feature of the convention included the definition of maritime zones- the territorial sea, the contiguous zone, the exclusive economic zone, the continental shelf, the high sea, the international sea-bed area and archipelagic waters. The convention also made provision for the passage of ships, protection of the marine environment, freedom of scientific research, and exploitation of resources.
Text of the treaty http://www.un.org/Depts/los/convention_agreements/texts/unclos/closindx.htm
List of countries that have ratified LOS conventions http://www.un.org/Depts/los/reference_files/chronological_lists_of_ratifications.htm