26 August 1966
On 26 August 1966, the People’s Liberation Army of Namibia (PLAN), the armed wing of SWAPO, fought in a battle against South African occupying forces at Omugulugwombashe in northern Namibia. In 1973 a resolution passed by the United Nations General Assembly declared 26 August, ‘Namibia Day’ to commemorate the gallant struggle of the Namibian people against the South African occupation of Namibia. On this date is also commemorated the anti-colonial war against Germany in the figure of Samuel Maharero. A Chief who fled to Botswana during the war and when his body was repatriated to Okahandja, central Namibia, a memorial event was held, a practice that continues to this day. This day is officially known as National Heroes Day in independent Namibia.
References

South African History Archives, (2013), Namibia Day [online] Available at www.SAHA.org.za [Accessed: 26 August 2013]