| | | | | | | | Oliver St John d. 1437 | | Margaret Beauchamp c. 1410–before 1482 | | John Beaufort 1404–1444 1st Duke of Somerset |
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| | | | John St John d. c. 1482 | | | | | | Oliver St John d. c. 1497 | | Margaret Beaufort 1443–1509 Countess of Richmond and Derby |
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| | | | John St John of Bletsoe c. 1450–after 1502 | | | | | | John St John | | King Henry VII 1457–1509 |
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| | | | John St John 1498–c. 1562 | | | | | | John St John 1473–1512 |
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| | | | Baron St John of Bletso, 1559 | | | | | | | | | |
| | | | Oliver St John 1516–1582 1st Baron St John of Bletso | | | | | | Nicholas St John d. 1589 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | Viscount Grandison of Limerick, 1620 Baron Tregoz of Highworth, 1626 |
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John St John d. 1596 2nd Baron St John of Bletso | | Oliver St John c. 1540–1618 3rd Baron St John of Bletso | | | | | | John St. John c. 1552–1594 | | | | | | | | | | Oliver St. John 1559–1630 1st Viscount Grandison and Baron Tregoz of Highworth |
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| | | | Earl of Bolingbroke, 1624 | | | | | | | St John Baronet, of Lydiard Tregoze, 1611 | | | | | | | | | | | See Villiers family tree |
| | | | Oliver St John c. 1580–1646 1st Earl of Bolingbroke, 4th Baron St John of Bletso | | Rowland St John 1588–1645 | | John St John 1585–1648 1st Baronet St John of Lydiard Tregoze | | | | | | Barbara St John | | Edward Villiers c. 1585–1626 |
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| | | | | | | | | | St John Baronet, of Woodford, 1660 | | | | | | | | | | |
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Oliver St John 1603–1642 5th Baron St John of Bletso | | Paulet St John d. 1638 | | Oliver St John c. 1624–1662 1st Baronet St John of Woodford | | Oliver St John 1612/1613 – November 1641 or 1642 | | Walter St John 1622–1708 3rd Baronet St John of Lydiard Tregoze |
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| | | | | | | | | | | | | | | | | | | | Viscount St John and Baron St John of Battersea, 1716 |
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Oliver St John before 1634–1688 2nd Earl of Bolingbroke, 6th Baron St John of Bletso | | Paulet St John 1634–1711 3rd Earl of Bolingbroke, 7th Baron St John of Bletso | | St Andrew St John c. 1650–1709 2nd Baronet St John of Woodford | | John St John 1638–1657 2nd Baronet St John of Lydiard Tregoze | | Henry St John baptized 1652–1742 1st Viscount St John, etc., 4th Baronet St John of Lydiard Tregoze |
| | | | Earldom of Bolingbroke extinct, 1711 | | | | | | | | | | | | | | | | | | | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | Viscount Bolingbroke and Baron St John of Lydiard Tregoze, 1712 | | | | | |
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Oliver St John c. 1683–1710 3rd Baronet St John of Woodford | | St Andrew St John c. 1685–1711 4th Baronet St John of Woodford | | William St John d. 1720 9th Baron St John of Bletso, 6th Baronet St John of Woodson | | Rowland St John d. 1722 10th Baron St John of Bletso, 7th Baronet St John of Woodson | | John St John d. 1757 11th Baron St John of Bletso, 8th Baronet St John of Woodson | | Henry St John 1678–1751 1st Viscount Bolingbroke, etc. | | | | | |
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| | | | Paulet St Andrew St John 1711–1714 8th Baron St John of Bletso, 5th Baronet St John of Woodford | | | | | | | | | | John St Andrew St John 1725–1767 12th Baron St John of Bletso, 9th Baronet St John of Woodson | | | | | | John St John 1702–1748 2nd Viscount St John, etc. |
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| | | | | | | | | | | | | | | | | | | | | | | | | Frederick St John 1732–1787 3rd Viscount St John, etc., 2nd Viscount Bolingbroke, etc., 5th Baronet of Lydiard Tregoze |
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| | | | | | | | | | | | | | | | Henry Beauchamp St John 1758–1805 13th Baron St John of Bletso, 10th Baronet St John of Woodson | | St Andrew St John 1759–1817 14th Baron St John of Bletso, 11th Baronet St John of Woodson | | George Richard St John 1761–1824 4th Viscount St John, 3rd Viscount Bolingbroke, etc., 5th Baronet of Lydiard Tregoze | | Ferdinand St. John 1804–1865 |
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| | | | | | | | | | | | | | | | | | | | St Andrew Beauchamp St John 1811–1874 15th Baron St John of Bletso, 12th Baronet St John of Woodson | | Henry St John 1786–1851 5th Viscount St John, 4th Viscount Bolingbroke, etc., 6th Baronet of Lydiard Tregoze | | Canon Maurice William Ferdinand St. John 1827–1914 |
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| | | | | | | | | | | | | | | | St Andrew St John 1840–1887 16th Baron St John of Bletso, 13th Baronet St John of Woodson | | Beauchamp Moubray St John 1844–1912 17th Baron St John of Bletso, 14th Baronet St John of Woodson | | Henry Mildmay St John 1820–1899 6th Viscount St John, 5th Viscount Bolingbroke, etc., 7th Baronet of Lydiard Tregoze | | Henry Percy St John 1854–1921•••• |
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| | | | | | | | | | | | Henry Beauchamp Oliver St John 1876–1920 18th Baron St John of Bletso, 15th Baronet St John of Woodson | | Moubray St Andrew Thornton St John 1877–1934 19th Baron St John of Bletso, 16th Baronet St John of Woodson | | Rowland Tudor St John | | Vernon Henry St John 1896–1974 7th Viscount St John, 6th Viscount Bolingbroke, etc., 8th Baronet of Lydiard Tregoze | | Geoffrey Robert St. John 1889–1972 |
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| | | | | | | | | | | | | | | | John Moubray Russell St John 1917–1976 20th Baron St John of Bletso, 17th Baronet St John of Woodson | | Andrew Beauchamp St John 1918–1978 21st Baron St John of Bletso, 18th Baronet St John of Woodson | | | | | | Kenneth Oliver Musgrave St John 1927–2010 8th Viscount St John, 7th Viscount Bolingbroke, etc., 9th Baronet of Lydiard Tregoze |
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| | | | | | | | | | | | | | | | | | | | Anthony Tudor St John b. 1957 22nd Baron St John of Bletso, 19th Baronet St John of Woodson | | Henry FitzRoy St John 1957–2011 9th Viscount St John, 8th Viscount Bolingbroke, etc., and 8th Baron St John of Battersea, 10th Baronet of Lydiard Tregoze | | | | | |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Nicholas Alexander Mowbray St John b. 1974 10th Viscount St John, 9th Viscount Bolingbroke, etc., 12th Baronet of Lydiard Tregoze |
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| | | | | | | | | | | | | | | | | | | | Oliver Beauchamp St John b. 1995 |