Barbara Palmer (1640–1709) 1st Duchess of Cleveland | | King Charles II (1630–1685) |
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| | | | | | | | | Duke of Monmouth Dukes of Buccleuch | | | Dukes of St Albans | | | |
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Dukes of Cleveland Dukes of Southampton | | | Duke of Northumberland | | Earl of Plymouth | | Dukes of Richmonds Dukes of Lennox |
| | Duke of Grafton, Earl of Euston, Viscount Ipswich and Baron Sudbury, 1675 |
| | Henry FitzRoy (1663–1690) 1st Earl of Euston 1st Duke of Grafton |
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| | Charles FitzRoy (1683–1757) 2nd Duke of Grafton |
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Charles Henry FitzRoy (1714–1715) Earl of Euston | | George FitzRoy (1715–1747) Earl of Euston | | Lord Augustus FitzRoy (1716–1741) |
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| | | | | | | | | | | | | Baron Southampton |
| | | | | | Augustus Henry FitzRoy (1735–1811) 3rd Duke of Grafton | | | | Charles FitzRoy (1737–1797) 1st Baron Southampton |
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| | | | | | George Henry FitzRoy (1760–1844) 4th Duke of Grafton | | | | George Ferdinand FitzRoy (1761–1810) 2nd Baron Southampton |
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| | | | | | Henry FitzRoy (1790–1863) 5th Duke of Grafton | | | | Charles FitzRoy (1804–1872) 3rd Baron Southampton |
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| | William Henry FitzRoy (1819–1882) 6th Duke of Grafton | | Augustus Charles Lennox FitzRoy (1821–1918) 7th Duke of Grafton | | Viscounts Daventry | | | |
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Henry James FitzRoy (1848–1912) Earl of Euston | | Alfred William Maitland FitzRoy (1850–1930) 8th Duke of Grafton | | Lord Charles Edward FitzRoy (1857–1911) | | Ismay FitzRoy (1863–1952) |
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| | | | William Henry Alfred FitzRoy (1884–1918) Viscount Ipswich | | | | Charles Alfred Euston FitzRoy (1892–1970) 10th Duke of Grafton |
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| | | | John Charles William FitzRoy (1914–1936) 9th Duke of Grafton | | | | Hugh Denis Charles FitzRoy (1919–2011) 11th Duke of Grafton |
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| | | | | | | | | | James Oliver Charles FitzRoy (1947–2009) Earl of Euston |
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| | | | | | | | | | Henry Oliver Charles FitzRoy (b. 1978) 12th Duke of Grafton |
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| | | | | | | | | | Alfred James Charles FitzRoy (b. 2012) styled Earl of Euston |
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