What was the primary resource the Zazzau shipped with the Hausa?

Explanation:

The Zazzau, also known as the Zaria Emirate, is a traditional state with headquarters in the city of Zaria, Kaduna State, Nigeria. The current emir of Zazzau is Alhaji Ahmed Nuhu Bamalli who succeeded the former emir, late Alhaji Shehu Idris.[1]

The most important source for the early history of Zazzau is a chronicle composed in the early 20th century from oral tradition. It tells the traditional story of the foundation of the Hausa kingdoms by the culture hero Bayajidda, and gives a list of rulers along with the length of their reigns. According to this chronology, the original Hausa or Habe kingdom is said to date from the 11th century, founded by King Gunguma.[2] This source also makes it one of the seven Hausa Bakwai states. Zazzau's most famous early ruler was Queen (or princess) Amina, who ruled either in the mid-15th or mid-16th centuries, and was held by Muhammed Bello, an early 19th-century Hausa historian and the second Sultan of Sokoto, to have been the first to establish a kingdom among the Hausa.[3]

Zazzau was a collection point for slaves to be delivered to the northern markets of Kano and Katsina, where they were exchanged for salt with traders who carried them north of the Sahara.[4] According to the history in the chronicle, Islam was introduced to the kingdom around 1456, but appears to have spread slowly, and pagan rituals continued until the Fulani conquest of 1808. At several times in its history, Zazzau was subject to neighboring states such as Songhai, Bornu and Kwararafa.[5]

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