Theophilus Ebenhaezer Dönges (8 March 1898 – 10 January 1968) was a South African politician who was elected the state president of South Africa, but died before he could take office, aged 69.

Eben Donges was born on 8 March 1898 in the town of Klerksdorp,^[2] the youngest son of Theophilus C. Dönges, a minister of religion. He attended Stellenbosch University and received a law degree from the University of London.^[2]: 698 He was admitted to the Middle Temple on 23 November 1921^[3] and withdrew without being called to the bar on 8 November 1928. When he returned from London, he became active in the National Party and joined its mouthpiece, Die Burger, as a journalist.^[2]: 698 He left journalism in 1927 and practised law.^[2]: 698

Dönges was a member of the Ossewabrandwag.^[4]

Running for parliament, he was unsuccessful in his first attempt in 1938 before obtaining a seat in 1941.^[2]: 698 When the National Party won power in 1948, he joined the cabinet as Minister of Posts and Telegraphs.^[2]: 698 As Minister of the Interior, from 1948 to 1961, he was one of the so-called "architects" of apartheid, introducing race-based population registration, and removing Coloured voters from the common voters' roll as a prelude to disenfranchising them altogether.^[2]: 698 During his tenure as Minister of the Interior, Dönges believed that apartheid would continue only for the next two generations. In November 1953, after DF Malan resigned as Cape Provincial leader, Dönges defeated Eric Louw to become the new provincial leader.^[5]

In the 1958 National Party leadership election following the death of Prime Minister J. G. Strijdom, Dönges ran for the party leadership and lost to Hendrik Verwoerd in the final round of voting between the two candidates.^[6] Despite this, Verwoerd included Dönges in the new cabinet as Minister of Finance from 1958 to 1966.^[2]: 698 After Verwoerd's assassination, Dönges, as a senior member of the Cabinet, became acting Prime Minister on 6 September 1966 until a National Party congress named B. J. Vorster to succeed to the premiership.^[2]: 698

Dönges was elected State President to succeed C.R. Swart on his retirement on 1 June 1967, but suffered a stroke and fell into a coma before he could take office.^[2]: 698 He died on 10 January 1968 without regaining consciousness.^[2]: 698 His deputy Tom Naudé acted for him until 6 December 1967 when he officially replaced Dönges.

He received the posthumous honours granted to a former State President: a state funeral and his effigy on the obverses of the 1969 silver 1 Rand coins. There is a school in Cape Town named after him, Eben Dönges High School and another primary school in Bothaville, Eben Dönges Primary School, as well as the Eben Dönges Hospital in Worcester.^[7]