Complex sentence: He was engaged in the struggle between the Mountain and the Girondists, and, after François Hanriot's "coup d'état" of 31 May 1793, he made himself conspicuous by his pursuit of the defeated Girondist party.
Split into simpler sentences: He was engaged in the struggle between the Mountain and the Girondists. After François Hanriot's "coup d'état" of 31 May 1793, he was conspicuous in his attack on the defeated Girondist party.