King George V. Anti-German sentiment during WWI caused him to change dynasty name from Saxe-Coburg Gotha to the House of Windsor. Older brother Prince Albert was in line for the throne, but died of pneumonia. George became successor and married his brother's fiance, Mary of Teck. Upon his death, his son Edward ascended the throne but later abdicated in favor of his relationship with American divorcee, Wallis Simpson. On that day "Bertie" became HM King George VI.