You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Nigeria

Context:
The name Nigeria was taken from the Niger River running through the country. This name was allegedly coined in the late 19th century by British journalist Flora Shaw, she was inspired by the name of the river, in preference to terms such as "Central Sudan". The origin of the name ''Nigeria'' came from the name of the Niger River. The word ( Niger )  is an alteration of the Tuareg name egerew n-igerewen used by inhabitants along the middle reaches of the river around Timbuktu prior to 19th-century European colonialism. Egerew n-igerewen means River of the Rivers.

Question:
What was Nigeria's region called by the British before the name Nigeria?

Central Sudan