Until the mid-18th century, officers rarely wore uniform. The Duke of Cumberland, King George II’s youngest son, forced Commanding Officers to make their officers do so. Military fashion increased from 1800. Uniform was regarded as work dress. Coats and hats look ornate today, but civil dress was more so. The Napoleonic wars confronted British soldiers with the finery of French uniforms. After Waterloo they began to adopt similar finery. George IV dressed the Household cavalry in bearskins and steel cuirasses (armor that covers the torso).
William IV had a passion for red into which he put the cavalry; The Hussars kept their blue but with red pelisses (long mantles or cloaks lined with fur). The Household cavalry were capped in bearskins so by 1830 the expense to officers of providing their own uniforms was so great economies had to be made. But the cavalry remained extravagant. Hussars went to Crimea with as much gold as before. That campaign demonstrated the unsuitability of ornate uniform on active service. In 1856 all were redesigned to assume a form which persisted until 1914. In 1939 full-dress wear at levees and special functions (except in the Household Brigade) finally died.