Table:
text: Governor-General of the Union of South Africa
List of governors-general of South Africa
List of governors-general of South Africa
_ Name_Birth_Death Took_office Left_office Monarch Prime_Minister_
1 The Viscount Gladstone , (1854–1930) 31 May 1910 8 September 1914 George V Botha
2 The Viscount Buxton , (1853–1934) 8 September 1914 17 November 1920 George V Botha
3 HRH Prince Arthur of Connaught , (1883–1938) 17 November 1920 21 January 1924 George V Smuts
4 The Earl of Athlone , (1874–1957) 21 January 1924 26 January 1931 George V Smuts
5 The Earl of Clarendon , (1877–1955) 26 January 1931 5 April 1937 George V Hertzog
6 Sir Patrick Duncan , (1870–1943) 5 April 1937 17 July 1943 George VI Hertzog

text: Governor-General of the Union of South Africa
List of governors-general of South Africa
List of governors-general of South Africa
_ Name_Birth_Death Took_office Left_office Monarch Prime_Minister_
— Nicolaas Jacobus de Wet , (1873–1960) , (Officer Administering the Government) 17 July 1943 1 January 1946 George VI Smuts
7 Gideon Brand van Zyl , (1873–1956) 1 January 1946 1 January 1951 George VI Smuts
8 Ernest George Jansen , (1881–1959) 1 January 1951 25 November 1959 George VI Malan
— Lucas Cornelius Steyn , (1903–1976) , (Officer Administering the Government) 26 November 1959 11 December 1959 Elizabeth II Verwoerd
9 Charles Robberts Swart , (1894–1982) 11 December 1959 30 April 1961 Elizabeth II Verwoerd
— Lucas Cornelius Steyn , (1903–1976) , (Officer Administering the Government) 30 April 1961 31 May 1961 Elizabeth II Verwoerd

Question: What was the total number of monarchs in the Union of South Africa governor general?