Question: From what years was Mansa Sandaki a mansa of an empire in West Africa?

Context paragraphs:
Mansa (title): Mansa is a Mandinka word meaning "sultan" (king) or "emperor".  It is particularly associated with the Keita Dynasty of the Mali Empire, which dominated West Africa from the thirteenth to the fifteenth century.  Powers of the mansa included the right to dispense justice and to monopolize trade, particularly in gold.

German West Africa: German West Africa ("Deutsch-Westafrika") was a designation used for the German Protectorates in West Africa between 1884 and 1919.  The term was normally used for the territories of Cameroon and Togo combined.  More rarely, German South West Africa was also subsumed under this name.  German West Africa existed only for a few years as an administrative unit.  However, in trade and in the vernacular the term was longer in use.

Maghan I: Maghan I was a mansa of the Mali Empire, following his father Kankan Musa I's death in 1337.  Aside from legendary founder Sundiata, Kankan Musa I is generally regarded as the most successful of the Malian emperors, and Maghan inherited the empire at the height of its glory.  He reigned for only four years before being succeeded by his uncle Suleyman in 1341.

List of colonial governors of South West Africa: The following is a list of colonial governors of South West Africa.  South West Africa was the colonial predecessor of the modern day Republic of Namibia from when the territory was controlled by the German Empire (as German South West Africa) and later by South Africa.

Miss West Africa: Miss West Africa is an international beauty pageant started in 2008 for females living in West Africa, as well as women of West African origin living around the world.  Entry is via regional Miss West Africa competitions, with the winner of each contest then competing at the Miss West Africa Final.  The first 2 competitions were held in London, and the event was held in Africa for the first time in the Gambia at the 2011 competition on 18 December 2011, which was won by Vanny Reis of Cape Verde.

Mali Empire: The Mali Empire (Manding: "Nyeni" or "Niani"; also historically referred to as the Manden Kurufaba, sometimes shortened to Manden) was an empire in West Africa from 1230 to 1670.  The empire was founded by Sundiata Keita and became renowned for the wealth of its rulers, especially Musa Keita.  The Manding languages were spoken in the empire.  It was the largest empire in West Africa and profoundly influenced the culture of West Africa through the spread of its language, laws and customs.  Much of the recorded information about the Mali Empire comes from 14th century North African Arab historian Ibn Khaldun, 14th century Moroccan traveller Ibn Battuta and 16th century Moroccan traveller Leo Africanus.  The other major source of information is Mandinka oral tradition, through storytellers known as griots.

Maghan III: Maghan III, also known as Mahmud I, was mansa of the Mali Empire from 1390 to about 1400.  He assumed the throne following the usurper Sandaki, who ruled for only two years.

Sandaki (mansa): Mansa Sandaki or Sandaki Mari Djata, also known as Sandiki or Santigi, was a mansa of the Mali Empire from 1389 to 1390.

Mande Studies Association: The Mande Studies Association (MANSA) is an international organisation open to all individuals with an academic or professional interest in the Mande region of West Africa.

Musa I of Mali: Musa Keita I (c. 1280 c. 1337 ) was the tenth "Mansa", which translates as "sultan" (king), "conqueror", or emperor of the wealthy West African Mali Empire.  At the time of Musa's rise to the throne, the Malian Empire consisted of territory formerly belonging to the Ghana Empire in present-day southern Mauritania and in Melle (Mali) and the immediate surrounding areas.  Musa held many titles, including "Emir of Melle", "Lord of the Mines of Wangara", "Conqueror of Ghanata", and at least a dozen others.  It is said that Mansa Musa had conquered 24 cities, each with surrounding districts containing villages and estates, during his reign.  During his reign Mali may have been the largest producer of gold in the world at a point of exceptional demand.  One of the richest people in history, he is known to have been enormously wealthy; reported as being inconceivably rich by contemporaries, "There’s really no way to put an accurate number on his wealth" (Davidson 2015).

Supporting paragraphs: Sandaki (mansa) Mali Empire
Answer: 1389 to 1390