The Nine Kings in order of seniority:
| Country | Sovereign | Born | Reigned | Died | |||||
| Greece | King George I | 24 December | 1845 | 27 June | 1863 | 18 March | 1913 | 18 March | 1913 |
| Spain | King Alfonso XIII | 17 May | 1886 | 17 May | 1886 | 14 April | 1931 | 28 February | 1941 |
| Bulgaria | King Ferdinand I | 26 February | 1861 | 7 July | 1887 | 3 October | 1918 | 10 September | 1948 |
| Germany | Emperor Wilhelm II | 27 January | 1859 | 15 June | 1888 | 18 November | 1918 | 4 June | 1941 |
| Norway | King Haakon VII | 3 Aug | 1872 | 18 November | 1905 | 21 September | 1957 | 21 September | 1957 |
| Denmark | King Frederik VIII | 3 June | 1843 | 29 January | 1906 | 14 May | 1912 | 14 May | 1912 |
| Portugal | King Manuel II | 19 March | 1889 | 1 February | 1908 | 4 October | 1910 | 2 July | 1932 |
| Belgium | King Albert I | 8 April | 1875 | 23 December | 1909 | 17 February | 1934 | 17 February | 1934 |
| United Kingdom | King George V | 3 June | 1865 | 6 May | 1910 | 20 January | 1936 | 20 January | 1936 |
If the photo were to have been recreated exactly one hundred years later, in May 2010, with all heirs to the nine kings assembled and sitting or standing in the same places, the following individuals would have been required, in most cases no more than two generations removed:
The Nine Kings' Heirs a Century Later, in order of seniority:
| Country | Sovereign (or Claimant) | Born | Reign(ed) (or Inherited Claim) | ||||
| Bulgaria | King Simeon II | 16 June | 1937 | 28 August | 1943 | 15 September | 1946 |
| United Kingdom | Queen Elizabeth II | 21 April | 1926 | 6 February | 1952 | ||
| Greece | King Constantine II | 6 June | 1940 | 6 March | 1964 | 8 December | 1974 |
| Denmark | Queen Margrethe II | 16 April | 1940 | 14 January | 1972 | ||
| Spain | King Juan Carlos I | 5 January | 1938 | 22 November | 1975 | ||
| Portugal | Dom Duarte, Duke of Braganza | 14 May | 1945 | 24 December | 1976 | ||
| Norway | King Harald V | 21 February | 1937 | 17 January | 1991 | ||
| Belgium | King Albert II | 6 June | 1934 | 9 August | 1993 | ||
| Germany | Prince Georg Friedrich of Prussia | 10 June | 1976 | 25 September | 1994 | ||
European Sovereigns, One Hundred Years Ago (1910) (1908)
European Sovereigns, Today
European Sovereigns
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