Complex sentence: De Gaulle began by making frequent use of "I" and "me" in his war-time speeches, but over time, their use declined while unlike Pétain de Gaulle never invoked quasi-religious imagery to enhance his prestige.
Split into simpler sentences: De Gaulle began by making frequent use of "I" and "me" in his war-time speeches, but over time, their use declined. Unlike Pétain, de Gaulle never invoked quasi-religious imagery to enhance his prestige.