King Taufa'ahau Tupou IV was the king of Tonga from 1965 until his death in 2006. He was born on July 4, 1918, and was the longest-reigning monarch in Tongan history. His reign was marked by significant political and social changes, including the introduction of a new constitution in 1875 that established a parliamentary system. During his time as king, Tupou IV focused on modernizing Tonga and improving the country's infrastructure. He was also known for his efforts in promoting education and healthcare. His leadership style was characterized by a blend of traditional Tongan values and modern governance practices.