Complex sentence: He met various Russian dignitaries including Prince Pyotr Mikhailovich Volkonsky, close advisor to Tsar Alexander I and Chief of the General Staff from 1815 to 1823, who resigned in 1824 after a conflict with War Minister Count Alexey Arakcheyev.
Split into simpler sentences: He met various Russian dignitaries including Prince Pyotr Mikhailovich Volkonsky, close advisor to Tsar Alexander I and Chief of the General Staff from 1815 to 1823. Volkonsky resigned in 1824 after a conflict with War Minister Count Alexey Arakcheyev.