Why did Richard, duke of York’s claim to the throne cause conflict in Parliament in 1460?

In 1460, Richard, 3rd Duke of York, formally claimed the English throne in Parliament by asserting his hereditary right as a descendant of Lionel, Duke of Clarence, the second surviving son of Edward III. This claim challenged the legitimacy of the reigning Lancastrian monarch, Henry VI, whose descent was through a younger son of Edward III.123

The claim caused significant conflict and hesitation within Parliament for several reasons:

• Constitutional Precedent: The House of Commons and the judges refused to adjudicate such a high matter, deferring the decision to the Lords, who debated the issue for a fortnight.3
• Prescription: While the Lords admitted York’s claim was legally unimpeachable based on strict lineal descent, they were wary of overturning a dynasty that had occupied the throne for three generations.2
• Political Instability: The claim effectively sought to disinherit Henry VI’s son, Prince Edward, which ensured the continued, fierce opposition of Queen Margaret of Anjou.14

Ultimately, Parliament reached a compromise—the Act of Accord—whereby Henry VI remained king for life, but Richard was recognized as his rightful successor.125