Complex sentence: Henry IV's rejection of the decree lead to his excommunication and a ducal revolt; eventually Henry received absolution after dramatic public penance barefoot in Alpine snow and cloaked in a hairshirt (see Walk to Canossa), though the revolt and conflict of investiture continued.
Split into simpler sentences: Henry IV's rejection of the decree lead to his excommunication and a ducal revolt. Eventually Henry received absolution after dramatic public penance barefoot in Alpine snow and cloaked in a hairshirt (see Walk to Canossa), though the revolt and conflict of investiture continued.