In 1527 the ambiguous policy followed by the second Medici Pope, Pope Clement VII, resulted in the dramatic sack of the city by the unruly Imperial troops of Charles V, Holy Roman Emperor. After the execution of some 1,000 defenders, the pillage began. The city was devastated for several days, many of the citizens were killed or took shelter outside the walls. Of 189 Swiss Guards on duty only 42 survived. The Pope himself was imprisoned for months in Castel Sant'Angelo. The sack marked the end of one of the most splendid eras of modern Rome.