Why did Henry IV declare war on Philip II of Spain in 1595?

Henry IV declared war on Philip II of Spain in January 1595 primarily to end Spanish interference in French internal affairs.1

Although Henry IV had converted to Roman Catholicism in 1593 and successfully entered Paris in 1594, Spain continued to provide military and financial support to the remaining resistance against his rule, most notably to the Holy League forces in Brittany led by Philippe-Emmanuel, Duke de Mercoeur. By declaring war, Henry aimed to eliminate these final pockets of opposition and neutralize the Spanish allies who were actively undermining his authority as king. The conflict concluded with the Treaty of Vervins in 1598, which solidified his position and brought an end to the long period of civil and religious strife in France.12