And speaking of Senegambia (except not really)....The short-lived French colony of Senegambia and Niger (1902-1904) was reorganized as Upper Senegal and Niger (1904-1921) and then as the colonies of Upper Volta, French Sudan, and Niger (Burkina Faso, the Republic of Mali, and the Republic of the Niger, respectively), all of which came under the governance of French West Africa. [And just to be clear, Senegambia and Niger did not include what would later become either Senegal or The Gambia, and bears no geographical resemblance to the short-lived Senegambia Confederation unifying the two.]
Stamp details: Stamp on top: Issued in: 1903 From: Bamako, Colony of Senegambia and Niger MC #1
Bottom left: Issued in: 1906 From: Bamako, Colony of Upper Senegal and Niger MC #7
Bottom right: Issued in: 1914 From: Bamako, Colony of Upper Senegal and Niger MC #18
Recognized as a sovereign state by the UN: No Claimed by: Burkina Faso; Republic of Mali; Republic of the Niger Member of the Universal Postal Union: No