| Country | Sovereign | Born | Acceded | Consort (born) | Heir (born) |
 Austro-Hungarian Empire |  Emperor Franz Joseph I | 18 Aug 1830 | 2 Dec 1848 |  Archduke Franz Ferdinand (1863) | |
 Principality of Liechtenstein |  Prince Johann II | 5 Oct 1840 | 12 Nov 1858 |  Prince Franz (1853) | |
 Kingdom of Montenegro |  King Nikola I | 7 Oct 1841 | 13 Aug 1860 |  Queen Milena (1847) |  Crown Prince Danilo (1871) |
 Kingdom of Romania |  King Carol I | 20 Apr 1839 | 20 Apr 1866 |  Queen Elisabeth (1843) |  Crown Prince Ferdinand (1865) |
 Kingdom of Spain |  King Alfonso XIII | 17 May 1886 | 17 May 1886 |  Queen Victoria Eugenie (1887) |  Infante Alfonso, Prince of Asturias (1907) |
 Kingdom of Bulgaria |  King Ferdinand I | 26 Feb 1861 | 7 Jul 1887 |  Queen Eleonore (1860) |  Crown Prince Boris (1894) |
 German Empire |  Emperor Wilhelm II | 27 Jan 1859 | 15 Jun 1888 |  Empress Auguste (1858) |  Crown Prince Wilhelm (1882) |
 Principality of Monaco |  Prince Albert I | 13 Nov 1848 | 10 Sep 1889 |  Her. Prince Louis (1870) | |
 Kingdom of the Netherlands |
 Queen Wilhelmina | 31 Aug 1880 | 23 Nov 1890 |  Prince Hendrik (1876) |  Princess Juliana (1909) |
 Russian Empire |  Emperor Nicholas II | 18 May 1868 | 1 Nov 1894 |  Empress Alexandra (1872) |  Tsarevich Alexei (1904) |
 Kingdom of Italy |  King Victor Emanuel III | 11 Nov 1869 | 29 Jul 1900 |  Queen Helena (1873) |  Crown Prince Umberto (1904) |
 Kingdom of Serbia |  King Peter I | 11 Jul 1844 | 12 Jun 1903 |  Crown Prince Alexander (1888) | |
 Kingdom of Norway |  King Haakon VII | 3 Aug 1872 | 18 Nov 1905 |  Queen Maud (1869) |  Crown Prince Olav (1903) |
 Kingdom of Sweden |  King Gustaf V | 16 Jun 1858 | 8 Dec 1907 |  Queen Victoria (1862) |  Crown Prince Gustaf Adolf (1882) |
 Ottoman Empire |  Sultan Mehmed V | 2/3 Nov 1844 | 27 Apr 1909 |  Crown Prince Yusuf Izzettin Efendi (1857) | |
 Kingdom of Belgium |  King Albert I | 8 Apr 1875 | 23 Dec 1909 |  Queen Elisabeth (1876) |  Prince Leopold, Duke of Brabant (1901) |
 United Kingdom of Great Britain and Ireland |  King George V | 3 Jun 1865 | 6 May 1910 |  Queen Mary (1867) |  Prince Edward, Prince of Wales (1894) |
 Grand Duchy of Luxemburg |  Grand Duchess Marie Adelaide | 14 Jun 1894 | 25 Feb 1912 |  Princess Charlotte (1896) | |
 Kingdom of Denmark |  King Christian X | 26 Sep 1870 | 14 May 1912 |  Queen Alexandrine (1879) |  Crown Prince Frederik (1899) |
 Kingdom of Greece |  King Constantine I | 2 Aug 1868 | 18 Mar 1913 |  Queen Sophie (1870) |  Crown Prince George (1890) |
German Rulers, 1913
| State | Ruler | Born | Acceded | ||
| Saxe-Meiningen | Duke Georg II | 2 Apr | 1826 | 20 Sep | 1866 |
| Bavaria | King Otto I | 27 Apr | 1848 | 13 Jun | 1886 |
| German Empire (Prussia) | Emperor (King) Wilhelm II | 27 Jan | 1859 | 15 Jun | 1888 |
| Württemberg | King Wilhelm II | 25 Feb | 1848 | 6 Oct | 1891 |
| Hesse | Grand Duke Ernst Ludwig | 25 Nov | 1868 | 13 Mar | 1892 |
| Waldeck & Pyrmont | Prince Friedrich | 20 Jan | 1865 | 12 May | 1893 |
| Mecklenburg-Schwerin | Grand Duke Friedrich Franz IV | 9 Apr | 1882 | 10 Apr | 1897 |
| Oldenburg | Grand Duke Friedrich August II | 16 Nov | 1852 | 13 Jun | 1900 |
| Saxe-Coburg & Gotha | Duke Carl Eduard | 19 Jul | 1884 | 30 Jul | 1900 |
| Saxe-Weimar-Eisenach | Grand Duke Wilhelm Ernst | 10 Jun | 1876 | 5 Jan | 1901 |
| Reuss (Senior Line) | Prince Heinrich XXIV | 20 Mar | 1878 | 19 Apr | 1902 |
| Anhalt | Duke Friedrich II | 19 Aug | 1856 | 24 Jan | 1904 |
| Mecklenburg-Strelitz | Grand Duke Adolf Friedrich V | 22 Jul | 1848 | 30 May | 1904 |
| Saxony | King Friedrich August III | 25 May | 1865 | 15 Oct | 1904 |
| Lippe | Prince Leopold IV | 30 May | 1871 | 13 Jan | 1905 |
| Baden | Grand Duke Friedrich II | 9 Jul | 1857 | 28 Sep | 1907 |
| Saxe-Altenburg | Duke Ernst II | 31 Aug | 1871 | 7 Feb | 1908 |
| Schwarzburg | Prince Günther | 21 Aug | 1852 | 28 Mar | 1909 |
| Schaumburg-Lippe | Prince Adolf II | 23 Feb | 1883 | 29 Apr | 1911 |
| Reuss (Junior Line) | Prince Heinrich XXVII | 10 Nov | 1858 | 29 Mar | 1913 |
(By May 1913, the Balkan League of Greece, Servia, & Bulgaria had already mostly expelled the Ottoman Empire from Europe, but borders were not entirely settled yet and most maps in use would have still looked like this.)