Good rare stamp.

South-West Africa was the name for modern-day Namibia when it was ruled by the German Empire. As a German colony from 1884, it was known as German South-West Africa. Germany had a difficult time administering the territory, which experienced many insurrections, especially those led by guerilla leader Jacob Morenga. The main port, Walvis Bay, and the Penguin islands were annexed by Britain as part of the Cape Colony in 1878, and became part of the Union of South Africa in 1910.As part of the Heligoland-Zanzibar Treaty in 1890, a corridor of land taken from the northern border of Bechuanaland, extending as far as the Zambezi river, were added to the colony. It was named the Caprivi Strip (Caprivizipfel) after the German Chancellor Leo von Caprivi.