Henry V of England of the influential John of Gaunt, and great-grandson of Edward III of England. At the time of his birth, Richard II, his first cousin once removed, was king. Henry's grandfather, John of Gaunt, was the king's guardian. As he was not close to the line of succession to the throne, Henry's date of birth was not officially documented; and for many years it was disputed whether he was born in 1386 or 1387. However, records indicate that his younger brother Thomas was born in the autumn of 1387 and that his parents were at Monmouth in 1386 but not in
The Twelve of England sealed by the marriage of John I of Portugal and Philippa of Lancaster, daughter of John of Gaunt) and before the death of John the Gaunt in 1399. Narrowing the window further, it was probably sometime after 1389, when John of Gaunt returned to England from his failed Iberian campaign, and before the death of John of Gaunt's wife, the Duchess of Lancaster, Constance of Castile in 1394. The common date frequently cited is 1390. The Duchess's Castilian nationality may lend credence to such an event, and her twelve ladies-in-waiting were also, likely, Castilian rather than English, which may explain