Half Second Cousin is in Second Cousin.
In 1109 Alfonso I King Aragon I King Pamplona 1073-1134 (age 36) and Urracca "Reckless" Jiménez Queen Consort Aragon and Pamplona (age 29) were married. She by marriage Queen Consort Aragon, Queen Consort Pamplona. She the daughter of Alfonso "Brave" VI King Leon VI King Castile (age 68) and Constance Burgundy Queen Consort Castile and Leon 1046-1093. He the son of Sancho Ramírez I King Aragon V King Pamplona and (age 49). They were half second cousins.
In 1112 Alfonso I King Aragon I King Pamplona 1073-1134 (age 39) and Urracca "Reckless" Jiménez Queen Consort Aragon and Pamplona (age 32) were divorced.
In or before 1120 Richard Avranches 2nd Earl Chester (age 26) and Lucia Mahaut Blois Countess Chester -1120 were married. She the daughter of Stephen Blois II Count Blois and Chartres 1045-1102 and Adela Normandy Countess Blois 1067-1137 (age 52). He the son of Hugh "Wolf Fat" Avranches 1st Earl Chester and . They were half second cousins. She a granddaughter of King William "Conqueror" I of England. 
Before 1140 Geoffrey Thouars IV Viscount Thouars (age 15) and Aenor Lusignan Viscountess Thouars (age 9) were married. She by marriage Viscountess Thouars. She the daughter of Hugh "Brown" Lusignan VII Count Lusignan II Count La Marche 1065-1151 (age 74) and . He the son of Aimery Thouars V Viscount Thouars and Agnes Poitiers Queen Consort Aragon 1105-1159 (age 34). They were half second cousins.
Before 15 Aug 1171 Ferdinand II King Leon 1137-1188 (age 34) and Urraca Burgundy Queen Consort Leon 1148-1211 (age 23) were married. She by marriage Queen Consort Leon. She the daughter of Afonso "Conqueror Founder Great" I King Portugal 1109-1185 (age 62) and Malfada Savoy Queen Consort Portugal 1125-1157. He the son of Alfonso VII King Castile VII King Leon 1105-1157 and Berenguela Barcelona Queen Consort Castile and Leon 1116-1149. They were half second cousins.
On 29 Aug 1189 King John "Lackland" of England (age 22) and Isabella Fitzrobert 3rd Countess Gloucester and Essex (age 16) were married at Marlborough Castle [Map]. He by marriage Earl Gloucester. She the daughter of William Fitzrobert 2nd Earl Gloucester -1183 and Hawise Beaumont Countess Gloucester. He the son of King Henry "Curtmantle" II of England and Eleanor of Aquitaine Queen Consort Franks and England (age 67). They were half second cousins. She a great granddaughter of King Henry I "Beauclerc" England. 
In 1334 William Hainault II Count Hainault (age 27) and Joanna Reginar Duchess Brabant 1322-1406 (age 12) were married. She the daughter of John Brabant III Duke Brabant 1300-1355 (age 33) and Marie Évreux Duchess of Brabant (age 31). He the son of William Hainault I Count Hainault III Count Avesnes III Count Holland II Count Zeeland (age 48) and Joan Valois Countess Zeeland Holland Avesnes and Hainault (age 40). They were half second cousins. He a great x 5 grandson of King Henry "Curtmantle" II of England. She a great granddaughter of King Edward "Longshanks" I of England.
Before 1336 John of Brabant (age 9) and Marie Valois were married. She the daughter of King Philip "Fortunate" VI of France (age 42) and Joan "Lame" Burgundy Queen Consort France 1293-1349 (age 42). He the son of John Brabant III Duke Brabant 1300-1355 (age 35) and Marie Évreux Duchess of Brabant. They were half second cousins. He a great grandson of King Edward "Longshanks" I of England. She a great x 4 granddaughter of King Henry "Curtmantle" II of England.
On 08 Jan 1345 Philip Duke Valois (age 8) and Blanche Évreux Queen Consort France 1331-1398 (age 14) were married. She the daughter of Philip "Noble" III King Navarre and Joan Capet II Queen Navarre (age 32). He the son of King Philip "Fortunate" VI of France (age 51) and Joan "Lame" Burgundy Queen Consort France 1293-1349 (age 51). They were half second cousins. He a great x 4 grandson of King Henry "Curtmantle" II of England. She a great x 3 granddaughter of King Henry III of England.
On 27 Aug 1349 Peter IV King Aragon (age 29) and Eleanor Barcelona Queen Consort Aragon were married. She by marriage Queen Consort Aragon. He the son of Alfonso IV King Aragon 1299-1336 and . They were half second cousins. He a great x 5 grandson of King Henry "Curtmantle" II of England. She a great x 5 granddaughter of King Henry "Curtmantle" II of England. 
On 19 Feb 1350 King John "The Good" II of France (age 30) and Joan Auvergne Queen Consort France 1326-1360 (age 23) were married. She by marriage Queen Consort of France. She the daughter of William Auvergne XII Count Auvergne II Count Boulogne 1300-1332 and Margaret Évreux Countess Auvergne and Boulogne 1307-1350. He the son of King Philip "Fortunate" VI of France (age 56) and Joan "Lame" Burgundy Queen Consort France 1293-1349. They were half second cousins. He a great x 4 grandson of King Henry "Curtmantle" II of England. She a great x 3 granddaughter of King Henry III of England.
Before 17 Sep 1388 Henry III King Castile 1379-1406 (age 8) and Catherine of Lancaster Queen Consort Castile (age 15) were married at Palencia Cathedral. She by marriage Queen Consort Castile. She the daughter of John of Gaunt 1st Duke Lancaster (age 48) and Constance of Castile Duchess of Lancaster (age 34). He the son of John I King Castile 1358-1390 (age 30) and Eleanor Barcelona Queen Consort Castile 1358-1382. They were half second cousins. She a granddaughter of King Edward III of England. 
In or before 1397 John Lovell 6th Baron Lovel (age 22) and Eleanor Zouche Baroness Lovel (age 31) were married. She by marriage Baroness Lovel of Titchmarsh. They were half second cousins. He a great x 5 grandson of King Henry "Curtmantle" II of England. 
On 25 Nov 1412 Henry "The Rich" Wittelsbach XVI Duke Bavaria 1386-1450 (age 26) and Margarete Habsburg Duchess Bavaria 1395-1447 (age 17) were married. She by marriage Duchess Bavaria. She the daughter of Albert Habsburg IV Duke Austria 1377-1404 and Joanna Sophia Wittelsbach Duchess Austria 1373-1410. He the son of Frederick Wittelsbach Duke Bavaria 1339-1393 and Maddalena Visconti Duchess Bavaria 1366-1404. They were half second cousins.
Around 1424 Archibald Douglas 2nd Duke Touraine (age 34) and (age 16) were married. She by marriage Duchess Touraine, Countess Wigtown. She the daughter of Patrick Graham and Eupheme Stewart 2nd Countess of Strathearn and Caithness -1434. He the son of Archibald Douglas 1st Duke Touraine (age 52) and Margaret Stewart Duchess Touraine. They were half second cousins.
On 18 Jul 1432 James "White Earl" Butler 4th Earl Ormonde (age 39) and Joan or Elizabeth Fitzgerald Countess Ormonde -1452 were married. She by marriage Countess Ormonde. She the daughter of Gerald Fitzgerald 5th Earl of Kildare -1432 and . He the son of James Butler 3rd Earl Ormonde 1359-1405 and Anne Welles Countess Ormonde 1360-1397. They were half second cousins. He a great x 3 grandson of King Edward "Longshanks" I of England. 
Before 1440 Edmund Grey 1st Earl Kent (age 23) and Katherine Percy (age 16) were married. She the daughter of Henry Percy 2nd Earl of Northumberland (age 46) and Eleanor Neville Countess Northumberland 1397-1472 (age 42). He the son of John Grey and Constance Holland Countess Norfolk and Nottingham 1387-1437. They were half second cousins. He a great x 2 grandson of King Edward III of England. She a great x 2 granddaughter of King Edward III of England. 
In 1447 Henry Holland 3rd Duke Exeter (age 16) and Anne York Duchess Exeter (age 7) were married. She the daughter of Richard Plantagenet 3rd Duke of York (age 35) and Cecily "Rose of Raby" Neville Duchess York (age 31). He the son of John Holland 2nd Duke Exeter (age 51) and Anne Stafford Duchess Exeter -1432. They were half second cousins. He a great x 2 grandson of King Edward III of England. She a great x 2 granddaughter of King Edward III of England. 
Before 03 Jul 1468 Charles "Bold" Valois Duke Burgundy (age 34) and Margaret of York Duchess of Burgundy (age 22) were married at Bruges. She the daughter of Richard Plantagenet 3rd Duke of York and Cecily "Rose of Raby" Neville Duchess York (age 53). He the son of Philip "Good" Valois III Duke Burgundy and Isabella Aviz Duchess Burgundy 1397-1471 (age 71). They were half second cousins. He a great x 2 grandson of King Edward III of England. She a great x 2 granddaughter of King Edward III of England. 
John Paston (age 24) and John Scott Comptroller (age 45) travelled with Margaret. The marriage re-enforced King Edward IV's connection with the Low Countries.
In 1472 Fernando II Duke of Braganza (age 42) and Isabella Aviz (age 13) were married. The difference in their ages was 29 years. They were half second cousins. She a great x 3 granddaughter of King Edward III of England.
In or before 1485 Nicholas St Lawrence 3rd Baron Howth (age 25) and Genet Plunkett Baroness Wenlock were married. She the daughter of Christopher Plunkett 2nd Baron Killeen and Elizabeth Welles Countess Kildare -1506. They were half second cousins.
In 1491 Robert Crichton 2nd Lord Crichton of Sanquhar (age 19) and Marion Margaret Maxwell (age 19) were married. They were half second cousins.
On 10 Apr 1502 King Frederick I of Denmark (age 30) and Anna of Brandenburg (age 14) were married. She the daughter of John "Cicero" Hohenzollern Elector Brandenburg 1455-1499 and Margaret of Thuringia. He the son of Christian I King Denmark 1426-1481 and Dorothea of Brandenburg. They were half second cousins.
Before 1509 David Kennedy 1st Earl Cassilis 1470-1513 (age 39) and Grisel aka Margaret Boyd Countess Cassilis were married. She by marriage Countess Cassilis. She the daughter of Thomas Boyd 1st Earl Arran and Mary Stewart Countess Arran. They were half second cousins. She a great x 4 granddaughter of King Edward III of England.
On 15 Feb 1510 William Fitzalan 18th Earl of Arundel (age 34) and Anne Percy Countess Arundel 1485-1552 (age 24) were married. She the daughter of Henry Percy 4th Earl of Northumberland and Maud Herbert Countess Northumberland 1458-1485. He the son of Thomas Fitzalan 17th Earl of Arundel (age 60) and Margaret Woodville Countess Arundel 1454-1490. They were half second cousins. He a great x 4 grandson of King Edward III of England. She a great x 4 granddaughter of King Edward III of England. 
In 1518 Thomas Neville (age 43) and Catherine Dacre (age 33) were married at Gilsland [Map]. They were half second cousins. He a great x 3 grandson of King Edward III of England. 
In 1524 Richard Catesby (age 24) and Dorothy Spencer (age 18) were married at Wormleighton. They were half second cousins.
In 1533 Henry Grey 1st Duke of Suffolk (age 16) and Frances Brandon Duchess of Suffolk (age 15) were married. She by marriage Marchioness Dorset. She the daughter of Charles Brandon 1st Duke of Suffolk (age 49) and Mary Tudor Queen Consort France (age 36). He the son of Thomas Grey 2nd Marquess Dorset and Margaret Wotton Marchioness Dorset (age 46). They were half second cousins. He a great x 5 grandson of King Edward III of England. She a granddaughter of King Henry VII of England and Ireland. 
On 01 Jul 1536 Richard Devereux (age 23) and Dorothy Hastings (age 20) were married. She the daughter of George Hastings 1st Earl Huntingdon (age 49) and Anne Stafford Countess Huntingdon (age 53). They were half second cousins. He a great x 5 grandson of King Edward III of England. She a great x 5 granddaughter of King Edward III of England. 
After May 1544 John Gordon 11th Earl Sutherland (age 19) and Elizabeth Campbell Countess Moray and Sutherland were married. She the daughter of Colin Campbell 3rd Earl Argyll 1486-1529 and Jean or Janet Gordon Countess Argyll. They were half second cousins. She a great x 5 granddaughter of King Edward III of England.
On 24 Feb 1545 Wolfgang Count Palatine of Zweibrücken (age 18) and Anna of Hesse aka Cleves (age 15) were married. She the daughter of Landgrave Philip I of Hesse 1504-1567 (age 40) and Christine of Saxony (age 39). They were half second cousins.
Before 10 Sep 1547 Robert Graham Master of Montrose and Margaret Fleming Countess Atholl 1529-1586 (age 18) were married. He the son of William Graham 2nd Earl Montrose 1492-1571 (age 55) and Janet Keith Countess Montrose -9999. They were half second cousins. She a great x 5 granddaughter of King Edward III of England.
Before 16 Apr 1548 Colin Campbell of Glenorchy (age 35) and Margaret Stewart were married. They were half second cousins. He a great x 4 grandson of King Edward III of England. She a great x 5 granddaughter of King Edward III of England.
On 12 Mar 1558 George Gordon 5th Earl Huntley -1576 and Anne Hamilton Countess Huntley 1535-1574 (age 23) were married. She the daughter of James Hamilton 2nd Earl Arran (age 42) and Margaret Douglas Duchess Châtellerault -1579. He the son of George Gordon 4th Earl Huntley 1514-1562 (age 44). They were half second cousins.
On 28 May 1571 Edward Bulstrode of Hedgerley Bulstrode Buckinghamshire and Cecily Croke (age 16) were married at St Dunstan's in the West, Fleet Street [Map]. They were half second cousins.
On 01 Dec 1577 Francis Stewart 5th Earl Bothwell (age 15) and Margaret Douglas Countess Bothwell were married. She by marriage Countess Bothwell. She the daughter of David Douglas 7th Earl Angus 1515-1558 and Margaret Hamilton Countess Angus 1585-1623. They were half second cousins. He a great x 2 grandson of King Henry VII of England and Ireland. 
In 1604 Philip Stanhope 1st Earl Chesterfield (age 20) and Catherine Hastings Countess Chesterfield were married. They were half second cousins.
Before 1628 Charles Berkeley 2nd Viscount Fitzhardinge (age 28) and Penelope Godolphin Viscountess Fitzhardinge were married. They were half second cousins.
Before 1647 Thomas Littleton 2nd Baronet (age 26) and Anne Littleton Lady Littleton were married. They were half second cousins.
In Dec 1668 John Kennedy 7th Earl Cassilis 1653-1701 (age 15) and Susannah Hamilton Countess Cassilis 1633-1694 (age 35) were married. She by marriage Countess Cassilis. The difference in their ages was 20 years. She the daughter of James Hamilton 1st Duke Hamilton and Mary Feilding Duchess Hamilton. He the son of John Kennedy 6th Earl Cassilis -1668 and Margaret Hay Countess Cassilis -1695. They were half second cousins.
After 1674 Thomas Fanshawe (age 46) and Elizabeth Fanshawe were married. They were half second cousins.
On 27 Mar 1676 John Brownlow 3rd Baronet (age 16) and Alice Sherard Baroness Brownlow (age 17) were married at Westminster Abbey [Map]. She by marriage Lady Brownlow of Humby in Lincolnshire. They were half second cousins.
Before 05 Sep 1686 William Lenthall and Catherine Hamilton (age 33) were married. They were half second cousins.
On 19 Oct 1692 Hugh Fortescue (age 27) and Bridget Boscawen were married. They were half second cousins.
Before 25 Feb 1702 Daniel Lascelles (age 46) and Mary Lascelles (age 40) were married. They were half second cousins.
Before 21 May 1758 Edward Smythe 4th Baronet (age 39) and Mary Clifford Lady Smythe (age 27) were married. They were half second cousins.
On 13 Apr 1773 William Burrell 2nd Baronet (age 40) and Sophia Raymond Lady Burrell (age 20) were married. The difference in their ages was 20 years. They were half second cousins.
On 19 Dec 1774 Charles Stanhope 3rd Earl Stanhope 1753-1816 (age 21) and Hester Pitt (age 19) were married. She the daughter of William "The Elder" Pitt 1st Earl Chatham (age 66) and Hester Granville Countess Chatham 1720-1803 (age 54). He the son of Philip Stanhope 2nd Earl Stanhope 1714-1786 (age 60) and Grizel Hamilton Countess Stanhope. They were half second cousins.
In 1781 Horatio Walpole 2nd Earl Orford 1752-1822 (age 28) and Sophia Churchill (age 25) were married. He the son of Horatio Walpole 1st Earl Orford 1723-1809 (age 57) and Rachel Cavendish (age 53). They were half second cousins.
On 25 Aug 1784 Henry Hoare 3rd Baronet (age 22) and Maria Palmer Acland were married. They were half second cousins.
On 04 Jul 1785 Thomas Dyke Acland 9th Baronet (age 33) and Henrietta Anne Hoare (age 22) were married. They were half second cousins.
Before 08 Jan 1797 Spencer Stanley Chichester (age 21) and Anne Harriet Stewart (age 28) were married. She the daughter of John Stewart 7th Earl Galloway 1736-1806 (age 60) and Anne Dashwood Countess Galloway 1743-1830 (age 54). He the son of Arthur Chichester 1st Marquess Donegal (age 57) and Anne Hamilton Countess Donegal 1738-1780. They were half second cousins.
On 24 Dec 1806 Samuel Hoare (age 23) and Louisa Gurney (age 22) were married at the Tasburgh Meeting House [Map]. They were half second cousins.
Before 07 Feb 1821 William Assheton Harbord 2nd Baron Suffield (age 54) and Caroline Hobart Baroness Suffield were married. She the daughter of John Hobart 2nd Earl Buckinghamshire and Mary Anne Drury Countess Buckinghamshire 1740-1769. They were half second cousins.
On 02 Oct 1837 George Edward Anson (age 25) and Georgiana Mary Harbord (age 25) were married. They were half second cousins.
On 21 Aug 1845 Edward Christopher Egerton (age 29) and Mary Frances Pierrepont were married. She the daughter of Charles Herbert Pierrepont 2nd Earl Manvers (age 67) and Mary Laetitia Eyre Countess Manvers 1784-1860 (age 60). They were half second cousins.
On 13 Jun 1846 John Henry Gurney (age 27) and Mary Jary Gurney (age 17) were married. They were half second cousins.
In 1858 Pascoe du Pré Grenfell (age 26) and Sophia Grenfell (age 27) were married. They were half second cousins.
On 07 Jun 1865 Ferdinand de Rothschild (age 25) and Evelina de Rothschild (age 25) were married. She died eighteen months later in childbirth. They were half second cousins.
On 15 Jun 1869 George Parker Heathcote (age 40) and Isabella Mararetta Elizabeth Walpole were married. They were half second cousins.
On 03 Apr 1877 John William Plunkett 17th Baron Dunsany (age 23) and Ernle Elizabeth Louisa Maria Grosvenor Burton (age 22) were married at St George's Church, Hanover Square. They were half second cousins.
On 25 Aug 1881 Richard Hanbury Joseph Gurney (age 26) and Sarah Evelyn Buxton were married. They were half second cousins.
On 08 Dec 1891 George Colborne Nugent (age 27) and Isabel Mary Bulwer (age 22) were married. They were half second cousins.
On 27 Oct 1892 Henry Waldegrave 11th Earl Waldegrave 1854-1936 (age 38) and Anne Katherine Bastard Countess Waldegrave (age 25) were married. They were half second cousins. He a great x 5 grandson of King James II of England Scotland and Ireland. 
On 14 Sep 1904 Geoffrey Duke Coleridge 3rd Baron Coleridge (age 27) and Mary aka Jessie Alethea Mackarness Baroness Coleridge (age 24) were married at St Michael's Church, Sandhurst. They were half second cousins.
On 23 Feb 1911 John Standish Surtees Prendergast 6th Viscount Gort (age 24) and Corinna Katherine Medlicott Vereker (age 19) were married. They were half second cousins.
Before 16 Jan 1916 Colonel Everard Charles Digby (age 63) and Emily Petty Fitzmaurice (age 61) were married. She the daughter of Henry Thomas Petty-Fitzmaurice 4th Marquess Lansdowne and . They were half second cousins.
On 11 Jul 1933 Charles Greville 7th Earl of Warwick 1911-1984 (age 22) and Rosa Bingham Countess Warwich and Brooke 1913-1972 (age 20) were married. She by marriage Countess Warwick, Countess Brooke Warwick Castle. He the son of Leopold Guy Greville 6th Earl Warwick 6th Earl Brooke 1882-1928 and Elfrida Marjorie Eden Countess Warwick and Brooke 1887-1943 (age 46). They were half second cousins.
In 1938 Charles Greville 7th Earl of Warwick 1911-1984 (age 26) and Rosa Bingham Countess Warwich and Brooke 1913-1972 (age 24) were divorced.
Ferdinand "Great" I King Leon 1015-1065 and Sancha Astur Leonese were married. She the daughter of Alfonso "Noble" V King Leon 994-1028 and . He the son of Sancho "Great" III King Pamplona 994-1035 and . They were half second cousins.
Robert Greystoke and Elizabeth Grey were married. She the daughter of Edmund Grey 1st Earl Kent and Katherine Percy. They were half second cousins. He a great x 3 grandson of King Edward III of England. She a great x 3 granddaughter of King Edward III of England. 
James I King Aragon and Eleanor Ivrea Queen Consort Aragon -1244 were married. She by marriage Queen Consort Aragon. She the daughter of Alfonso VIII King Castile 1155-1214 and Eleanor Plantagenet Queen Consort Castile 1161-1214. He the son of Peter II King Aragon 1178-1213 and . They were half second cousins. She a granddaughter of King Henry "Curtmantle" II of England.
Bermudo III King Leon 1015-1037 and Jimena Sánchez Jiménez Queen Consort Leon were married. She the daughter of Sancho "Great" III King Pamplona 994-1035 and . He the son of Alfonso "Noble" V King Leon 994-1028 and . They were half second cousins.
Robert Kerr 2nd Earl Lothian 1574-1624 and Annabel Campbell Countess Lothian -1652 were married. She the daughter of Archibald Campbell 7th Earl Argyll and Agnes Douglas Countess Argyll 1574-1607. He the son of Mark Kerr 1st Earl Lothian 1553-1609. They were half second cousins.
