, commonly characterized as 'Mad King George', was Great Britain's longest-reigning king. He ascended the throne in 1860, and during his almost 60-year monarchy, he was both revered and reviled. Despite the turbulence of war, Britain prospered under his reign and experienced significant scientific and technological advancements. Unfortunately, his life has become primarily defined by his health: but did George III actually have porphyria, as popularized in Alan Bennett's The Madness of King George? Did you know that official and personal documents, recently made accessible through the Georgian Papers Programme, have provided intriguing new insight into King George III's reign and health? George III experienced significant recurrent episodes of mental and physical illness. During these, he talked incessantly and obscenely, acted erratically and lewdly, and suffered from insomnia and hallucinations. 1 One of his doctors wrote, 'Rex noster insanit' or 'our King is mad'. 2 Records indicate that he also had pain in his abdomen and joints, muscle weakness, and rash. The cause of George III's 'madness' has been the subject of substantial speculation. In 1966, the psychiatrists Macalpine and Hunter claimed that George III had recurrent attacks of acute intermittent porphyria. 3 Their archival research focused on certain physical manifestations of the king's illness, particularly the incidences of discolored urine. They subsequently changed their diagnosis to variegate porphyria, asserting that this inherited metabolic disorder could be identified in other generations of the king's lineage. 4 Despite some skepticism, the porphyria hypothesis was widely accepted by historians, medical experts, and even popular culture. Alan Bennett's The Madness of King George and its 1994 Oscar-nominated movie adaptation portray the story of the king's declining health and the ensuing betrayals by politicians and the Royal family. The arts generated awareness of porphyria and popularized its role in the deteriorating mental health of the king. Recent studies, however, indicate that the evidence for a diagnosis of porphyria is weak and that Macalpine and Hunter's interpretation is flawed. Using cognitive archaeology, handwriting analysis, and computer diagnostics of documents released through the Georgian Papers Programme, experts now conclude that George III had bipolar disorder. 5,6 George III wrote, 'I spend money on war because it is necessary, but to spend it on science, that is pleasant to me'. 7 Interestingly, it is through the advancement of science and technology that modern-day society may finally have a better understanding of King George III.