Cilliers (12 January 1865 – 1 June 1940) was an Afrikaans-language poet, essayist, dramatist and reviewer.
Celliers was one of the three outstanding Afrikaans-language poets who wrote in the immediate wake of the Second Boer War; together with Totius and C. Louis Leipoldt, Celliers' youthful poetry writes of the devastation of the war in the youthful language of Afrikaans.
Celliers was born near Wellington, Cape Colony.
After a childhood near Cape Town, Celliers and his family moved to Pretoria, in the then-country of Transvaal in 1874.
Escaping through British lines wearing his wife's clothes, Celliers went to Europe until his 1907 return to South Africa.