In a dramatic assertion of Welsh identity and autonomy, Owain Glyndŵr was declared Prince of Wales by his followers, igniting a fervent nationalist movement across Wales. Glyndŵr, a member of the historical Welsh gentry, rose to prominence following the oppressive policies implemented by the English King Henry IV. His declaration was not merely a title; it symbolized a collective aspiration among the Welsh for self-determination and control over their own destiny, amidst increasing resentment towards English rule. This act was a rallying point for many discontented Welsh citizens who were eager to challenge the status quo and reclaim their heritage.

The proclamation was made in the context of a broader rebellion known as the Glyndŵr Rising, which began soon after his declaration. Glyndŵr's leadership galvanized support from various factions across Wales, leading them to rise against the English crown. The movement saw initial military successes, and Glyndŵr was able to establish himself as a formidable leader, even managing to engage in negotiations with the French, which heightened the conflict's international dimension. His followers claimed legitimacy through the historical connection of Welsh kingship, invoking cultural symbols and memories of past independence.

However, the proclamation also set in motion a series of brutal confrontations with the English forces, which started a prolonged struggle for Welsh independence. Despite early victories, including the capture of significant fortresses, the overwhelming resources of the English crown would ultimately lead to the decline of Glyndŵr's uprising by the early 15th century. Nevertheless, his declaration marked a critical juncture in Welsh history, cementing his place as a national figure and setting the foundation for future assertions of Welsh identity and sovereignty.