Complex sentence: Jeffreys returned to London after the Assizes to report to King James, who rewarded him by making him Lord Chancellor (at the age of only 40),'For the many eminent and faithful services to the Crown'.
Split into simpler sentences: Jeffreys returned to London after the Assizes to report to King James. He rewarded him by making him Lord Chancellor (at the age of only 40),'For the many eminent and faithful services to the Crown'.