He was proclaimed king at the Zealand Assembly (Danish:landsting) in 1076. Harald was dependent on the great nobles of Denmark for his election and did nothing to oppose them. As a result, he fought no wars and spent his energy improving the few things that lay in his perview. On the whole he was a peaceful and able ruler. He is best known for improving and standardizing Danish coinage. He established mints at Ribe , Viborg, Lund, and Schleswig. Harald's second accomplishment was changing Danish legal customs. Harald deplored the ancient customs of trial by ordeal and trial by combat. He introduced a system used by the English of calling upon honorable men to make oaths in behalf of the parties in a trial, rather than resort to the "ancient" customs of holding red-hot iron bars or trial by combat. However, his reforms were not fully accepted until the reign of Valdemar II. Saxo Grammaticus) scorned him as a weak and ineffective king yielding to the will of the common people. Perhaps this gives the explanation for his nickname Harald the Whetstone (Danish: Harald Hen or Hejn), in other words, Harald the soft.
Later historians regard him as a "democratic" monarch for the same reasons.