Public holidays in Rhodesia weekend". Shangani Day was replaced as a public holiday by Occupation Day in 1920, but continued to be unofficially marked thereafter. Occupation Day, held on 12 September each year, marked the anniversary of the arrival of the Pioneer Column at Fort Salisbury in 1890, and their raising of the Union Jack on the kopje overlooking the site. It was renamed Pioneers' Day in 1961. Southern Rhodesia effectively became the entirety of Rhodesia in 1964 when Northern Rhodesia became independent as Zambia. After Southern Rhodesia's colonial government unilaterally declared independence from Britain on 11 November 1965, the anniversary became celebrated as
Southern Rhodesia an Interpretation Bill to declare that the colony could be referred to as Rhodesia. The Bill received its third reading on 9 December 1964, and passed to the Governor for assent. However, no assent was granted to the Bill. Section 3 of the Southern Rhodesia (Annexation) Order 1923 provided that Southern Rhodesia "shall be known as the Colony of Southern Rhodesia" and the Southern Rhodesia (Constitution) Act 1961 and the Order-in-Council which followed it both referred to it as such. These were United Kingdom measures and it was outside the powers of Southern Rhodesian institutions to amend them. The Rhodesian