Alonso

Alonso is a Spanish name of Germanic origin that is a Castilian variant of ''Adalfuns''. The original Visigothic name ''Alfonso'' suffered the phonetic change of the phoneme /f/ into the mute /h/ in the Early Middle Ages (around 9th Century), what eventually suppressed the sound /f/ from the name, deriving in the modern form ''Alonso''. Due to the demographic particularities of the Iberian peninsula during the Middle Ages, this phonetic change was not uniform across the territory and the original form ''Alfonso'' also survived in different areas. Therefore, today both forms of the name coexist in Spanish speaking countries. Provided by Wikipedia