1 Real Vicente Guerrero - Insurgent Countermarked coinage

During the final phase of the Mexican War of Independence, insurgent commanders operating outside royalist-controlled mints needed circulating money their forces and sympathizers would accept. Guerrero's forces — active in the rugged terrain of what is now Guerrero state — applied countermarks to existing royalist reales, effectively converting crown coinage into insurgent currency through a single punch. The practice was improvised, decentralized, and varied enough that no two countermarked pieces are quite alike in placement or depth of strike.

KM#277 encompasses a range of host coin dates, which is why the spread runs across nearly six years.