January - Henry IV quells the Epiphany Rising and executes the Earls of Kent, Huntingdon and Salisbury and the Baron le Despencer for their attempt to have Richard II restored as King.
14 February - Death of the deposed Richard II in Pontefract Castle. His body is displayed in old St Paul's Cathedral, London, on 17 February before initial burial in Kings Langley Church on 6 March.
February - Henry Percy (Hotspur) leads English incursions into Scotland.
25 July - English invasion of Scotland (1400): Henry IV leads his army north from a muster at York.
Mid-August - The English army camp at Leith near Edinburgh but fail to besiege Edinburgh Castle.
16 September - Owain Glyndŵr is proclaimed Prince of Wales by his followers and begins attacking English strongholds in north-east Wales.
24 September - Welsh rebels invade England, but are turned back at Welshpool.
October - Henry launches a punitive campaign against north Wales.
December - Manuel II Palaiologos becomes the only Byzantine Emperor ever to visit England, being entertained at Eltham Palace.
1401
Passing of the De heretico comburendo Act — the Archbishop of Canterbury pressures King Henry IV into outlawing as heretics anyone owning an English translation of the Bible. Death by burning is the punishment for heresy.
2 March - William Sawtrey, a Lollard, is the first person to be burned at the stake at Smithfield.
June - Battle of Hyddgen; outnumbered three to one, Welsh rebels defeat Anglo-Flemish force near Aberystwyth.
June - English Pale in Ireland reduced to Dublin, County Kildare, County Louth, and County Meath.
3 November - Battle of Twthill near Caernarfon; English and Welsh forces both sustain losses with no clear victor.
December - Glyndŵr firmly establishes control over northern Wales.
1402
22 June
Battle of Nesbit Moor: An English force decisively defeats a returning Scottish raiding party.
Battle of Bryn Glas: Welsh rebels defeat the English on the England/Wales border.
August - Glamorgan joins Glyndŵr's revolt.
14 September - Battle of Humbleton Hill: Northern English nobles led by Sir Henry Percy (Hotspur) and using longbows decisively defeat a Scottish raiding army and capture their leader, the Earl of Douglas.
1403
7 February - King Henry IV of England marries as his second wife Joan of Navarre, the daughter of King Charles II of Navarre and widow of John IV, Duke of Brittany, at Winchester Cathedral.
21 July - Battle of Shrewsbury: Henry IV defeats a rebel army led by "Hotspur" Percy who has allied with the Welsh rebel Owain Glyndŵr. Percy is killed in the battle by an arrow in his face.
A guild of stationers is founded in the City of London. As the Worshipful Company of Stationers and Newspaper Makers (the "Stationers' Company"), it continues to be a Livery Company in the 21st century.
1404
14 January - Henry grants Parliament the power to appoint Royal Councillors and hold them to account for expenditure.
10 May - Glyndŵr holds a Parliament at Dolgellau.
14 June - Owain Glyndŵr, having declared himself Prince of Wales, allies with the French against the English.
6 October - Parliament meets at Coventry; Henry withdraws its powers of oversight over the Royal Council.
1405
11 March - Battle of Grosmont (Monmouthshire): English defeat Welsh rebels.
April - Archbishop of York Richard Scrope joins Henry Percy, 1st Earl of Northumberland, and Lord Bardolf in a rebellion in northern England.
5 May - Battle of Usk: English defeat Welsh rebels.
8 June - Following the collapse of their revolt, Richard Scrope together with Thomas de Mowbray, 4th Earl of Norfolk, and Scrope's nephew, Sir William Plumpton, are tried by a special commission and beheaded at York. Scrope is the first English prelate to suffer judicial execution.
August - Welsh rebels, assisted by the French, unsuccessfully attack Worcester.
Hundred Years' War: French attack Aquitaine.
1406
1 March - Parliament meets, and continues to sit until December, when it finally achieves its aims of nominating and ensuring the payment of members of the Royal Council.
30 March - The heir to the Scottish throne, Prince James, having been captured by English pirates on 22 March, is detained in England.
13 October - Richard Whittington is elected as Lord Mayor of London for his second full term.
English ships attack Brodick Castle on the Isle of Arran.
Eric of Pomerania marries Philippa, daughter of Henry IV.
Richard, Earl of Cambridge, marries Anne de Mortimer.
1407
October - Henry, Prince of Wales, besieges Welsh rebels at Aberystwyth.
Central tower of York Minster collapses.
David Holbache founds Oswestry School.
1408
February - Henry Percy, 1st Earl of Northumberland, and Lord Bardolf advance with troops from exile in Scotland to Thirsk where they issue a proclamation that they have come to relieve the people from unjust taxation.
19 February - Battle of Bramham Moor: Thomas de Rokeby, Sheriff of Yorkshire, suppresses the Percy rebellion in the north, Percy and Bardolf both being killed.
September - Henry, Prince of Wales, retakes Aberystwyth from Owain Glyndŵr.
Glass painter John Thornton of Coventry completes the largest medieval window in England, at York Minster.
1409
c. January - The Welsh surrender Harlech Castle to the English.
28 February - Henry, Prince of Wales, appointed Constable of Dover and Warden of the Cinque Ports.
Beverley Bar built as the North Gate of Beverley in the East Riding of Yorkshire.
Births
1400
25 December - John Sutton, 1st Baron Dudley, Lord Lieutenant of Ireland (died 1487)
Richard Neville, 5th Earl of Salisbury, English politician (died 1460)
1401
26 November - Henry Beaufort, 2nd Earl of Somerset (died 1418)
1402
15 August - Humphrey Stafford, 1st Duke of Buckingham (died 1460)
1403
Robert Wingfield, politician (died 1454)
1404
25 March (baptism) - John Beaufort, 1st Duke of Somerset, military leader (died 1444)
1406
26 September - Thomas de Ros, 8th Baron de Ros, soldier and politician (died 1430)
1407
Thomas de Littleton, judge (born c. 1407)
1408
23 April - John de Vere, 12th Earl of Oxford (died 1462)
John FitzAlan, 14th Earl of Arundel (died 1435)
Deaths
1400
5 January
John Montacute, 3rd Earl of Salisbury, politician (executed) (born 1350)
Thomas Holland, 1st Duke of Surrey, politician (executed) (born 1374)
13 January - Thomas le Despenser, 1st Earl of Gloucester, politician (executed) (born 1373)
16 January - John Holland, 1st Duke of Exeter, politician (executed) (born c. 1352)
14 February - King Richard II (possibly murdered) (born 1367)
21 August - Henry Yevele, master mason (born c. 1320)
25 October - Geoffrey Chaucer, poet (born c. 1343)
Ralph Strode, scholar (born 1350)
1401
March - William Sawtrey, Lollard martyr (burned at the stake) (year of birth unknown)
8 April (or 8 August) Thomas de Beauchamp, 12th Earl of Warwick (born 1338)
1402
1 August - Edmund of Langley, 1st Duke of York, son of King Edward III (born 1341)
1403
10 May - Katherine Swynford, widow of John of Gaunt (born c. 1350)
12 May - William de Lode, prior (year of birth unknown)
21 July
Henry Percy, soldier (killed in battle) (born 1364/1366)
Edmund Stafford, 5th Earl of Stafford (killed in battle) (born 1378)
23 July - Thomas Percy, 1st Earl of Worcester, rebel (executed) (born 1343)
1404
27 September - William of Wykeham, bishop and statesman (born 1320)
1405
12 January - Eleanor Maltravers, noblewoman (born 1345)
17 August - Thomas West, 1st Baron West (born 1335)
1406
6 January - Roger Walden, bishop (year of birth unknown)
1408
20 February - Henry Percy, 1st Earl of Northumberland, statesman (born 1342)
Elizabeth le Despenser, noblewoman (year of birth unknown)
1409
22 May - Blanche of England, sister of King Henry V (born 1392)
Thomas Merke, bishop (year of birth unknown)
Sir Edmund Mortimer, son of the 3rd Earl of March, rebel (born 1376)
