In 1876, Fort Amiel was constructed as a defence against the Zulus.
Newcastle was initially called Post Halt Number 2 on maps during the 1840s, a stopover on the journey between Durban and Johannesburg.
The name emanates from the British Colonial Secretary, the fifth Duke of Newcastle.
The Boer invaded Newcastle on 14 October 1899 and the district was incorporated into the Transvaal. The worn was renamed Viljoensdorp after General Ben Viljoen. Its name was restored bu General Buller.
The town was used as a depot by the British during both the First and Second Boer War.
British preparation work for the Pretoria Convention of 1881 was undertaker here.
The War memorial at Newcastle can be seen
here.