Henry V (16 September 1386 – 31 August 1422), also called Henry of Monmouth, was King of England from 1413 until his death in 1422. Despite his relatively short reign, Henry's outstanding military successes in the Hundred Years' War against France made England one of the strongest military powers in Europe. Immortalised in Shakespeare's "Henriad" plays, Henry is known and celebrated as one of the greatest warrior-kings of medieval England.

During the reign of his father Henry IV, Henry gained military experience fighting the Welsh during the revolt of Owain Glyndŵr and against the powerful aristocratic Percy family of Northumberland at the Battle of Shrewsbury. Henry acquired an increasing role in England's government due to the king's declining health, but disagreements between father and son led to political conflict between the two. After his father's death in 1413, Henry assumed control of the country and asserted the pending English claim to the French throne.

In 1415, Henry embarked on war with France in the ongoing Hundred Years' War (1337–1453) between the two nations. His military successes culminated in his famous victory at the Battle of Agincourt (1415) and saw him come close to conquering France. Taking advantage of political divisions within France, he conquered large portions of the kingdom, resulting in Normandy's occupation by the English for the first time since 1345–1360. After months of negotiation with Charles VI of France, the Treaty of Troyes (1420) recognised Henry V as regent and heir apparent to the French throne, and he was subsequently married to Charles's daughter, Catherine of Valois. Everything seemed to point to the formation of a union between the kingdoms, in the person of Henry. However, he died two years later and was succeeded by his only child, the infant Henry VI.