The history of the Western Sahara is strongly connected to the ones of its neighbours, especially Morocco and Mauritania. The definitive status of this former Spanish Colony did not find any legal solution yet, more than 30 years after the departure of Spanish administration. Here is a more detailed historical fact sheet about this conflict, from the 60's to nowadays

1965
Resolution 2072 of the UN General Assembly: the Sahara appears on the list of regions to decolonize (resolution 1514 on the right to self-determination of colonized peoples)

May 10, 1973
Creation of the Polisario Front, the popular front for the Liberation of Saguia El Hamra and Rio de Oro, that demands independence

1975
The International Court of Justice in The Hague rejects Morocco and Mauritania’s alleged “historical claim” on Western Sahara

November 6, 1975
The Green march: 350,000 Moroccan civilians invade Saharawi territory.

November 14, 1975
Madrid Accords signed by Spain, Morocco, and Mauritania asserting Spain’s withdrawal by 28 February 1976 and the division of territory between Rabat and Nouakchott

February 27, 1976
Polisario Front declares the Saharawi Arab Democratic Republic (SADR)

August 5, 1979
Mauritania and Polisario sign a peace agreement, in Algiers, by which Mauritania renounces its claim to the Western Sahara. Moroccan forces annex the area left by the Mauritanian army

1981
Construction of an approximately 2,700 km-long defensive
wall to separate Polisario-controlled sections and Saharawi
refugees (in exile in Tindouf) from the rest of the Saharawi
population

November 12, 1984
Morocco leaves the Organisation of African Unity following
admission of the SADR at the Addis Ababa summit

August 30, 1988
The UN brokers a peace plan that both protagonists accept:
a ceasefire, the organization of a referendum on
self-determination and the deployment of a peacekeeping
mission, MINURSO

1991
The UN Security Council unanimously approves the settlement plan, which is based on the Spanish 1974 census of the Saharawi population (74,000 people)

September 6, 1991
The ceasefire goes into force and MINURSO established to ensure the plan is respected

1997
Former US Secretary of State James Baker nominated United Nations Special Representative to resolve the dispute between Moroccans and Saharawis regarding the issue of the electoral body authorized to decide upon the territory’s future

June 2001
Plan Baker I rejected by the Polisario and Algeria

January 2003
Plan Baker II calls for the holding of a referendum on self-determination after a four-to-five-year period of internal self-governance. Rejected by Morocco

July 2005
Peter Van Waslum nominated personal envoy of the UNSG

April 2007
Presentation of the Moroccan Autonomy Plan for Western Sahara to the United Nations. Adoption of resolution 1754

June 2007
First round of negotiations between Morocco and the Polisario Front, in the presence of neighboring states Algeria and Mauritania, in Manhasset (New York).

August 2007
Second round of negotiations

October 2007
Adoption of resolution 1783: mandate of Minurso extended until April 30, 2008, to organize the referendum of Western Sahara

April 2008
Adoption of resolution 1813 : mandate of Minurso extended until April 30, 2009, to organize the referendum of Western Sahara

January 14, 2009 
Christopher Ross nominated Special Envoy of the UNSG