1420

1420 is a year in the 15th century, notable in European history for political developments arising from the Hundred Years’ War. The Treaty of Troyes, concluded in 1420, recognized Henry V of England as the heir and regent of France and disinherited the Dauphin, Charles VII. This agreement strengthened an Anglo-French alliance during a period of intense conflict and contest over the French throne. In the same year, Henry V married Catherine of Valois, a union that reinforced the political settlement between England and parts of France and influenced succession considerations in the years that followed.

As a number, 1420 is a composite integer. Its prime factorization is 2^2 × 5 × 71, making it divisible by 4 and by 5, and its other divisors include 1, 2, 4, 5, 10, 14, 20, 71, 142, 284, 355, and 710. In Roman numerals, 1420 is written as MCDXX. It lies between 1419 and 1421 and is used in various modern contexts as a year designation or numerical identifier.

The year’s historical importance lies primarily in its diplomatic and dynastic implications, shaping the balance of power in western Europe during the latter part of the Hundred Years’ War. Beyond this, 1420 is commonly referenced in numerical contexts as part of chronological sequences and cataloging systems.