William IV and Queen Adelaide, 1881.

King William IV (1765-1837) and Queen Adelaide (1792-1849), 1881. William was King of the United Kingdom of Great Britain and Ireland from 1830 until his death in 1837. His reign was one of several reforms: the poor law was updated, child labour was restricted, slavery was abolished throughout the British Empire. and the 1832 Reform Act refashioned the British electoral system. He married Adelaide in 1818. In the absence of a legitimate heir, however, he was succeeded by his niece, Victoria. (Photo by The Print Collector/Print Collector/Getty Images)