What is the date in history that the western Sahara became a state or an independent?

Western Sahara has not been universally recognized as an independent state. It was formerly a Spanish colony and was claimed by Morocco and Mauritania after Spain withdrew in 1975. The Sahrawi Arab Democratic Republic (SADR) was proclaimed by the Polisario Front on February 28, 1976, but it remains partially recognized and is considered a non-self-governing territory by the United Nations. The quest for independence continues to this day.