Which two nations were involved in a year-long conflict that was popularly known as the Pastry War?

The Pastry War (Spanish: Guerra de los pasteles, French: Guerre des Pâtisseries), also known as the First French intervention in Mexico or the First Franco-Mexican War (1838–1839), began in November 1838 with the naval blockade of some Mexican ports and the capture of the fortress of San Juan de Ulúa in Veracruz by French forces sent by King Louis-Philippe. It ended several months later in March 1839 with a British-brokered peace. The intervention followed many claims by French nationals of losses due to unrest in Mexico.

This incident was the first and lesser of Mexico's two 19th-century wars with France, being followed by the French invasion of 1861–67 which supported the short reign of Emperor Maximilian I of Mexico who was executed by firing squad at the end of that later conflict.