“First documented instance of a princess who wore a white wedding gown for a royal wedding ceremony is that of Philippa of England, who wore a tunic with a cloak in white silk bordered with grey squirrel and ermine in 1406.
Mary, Queen of Scots, wore a white wedding gown in 1559 when she married her first husband, Francis Dauphin of France, because it was her favorite color, although white was then the color of mourning for French Queens.
This was not a widespread trend, however: prior to the Victorian era, a bride was married in any color, black being especially popular in Scandinavia.
White became a popular option in 1840, after the marriage of Queen Victoria to Albert of Saxe-Coburg, when Victoria wore a white gown to incorporate some lace she prized. The official wedding portrait photograph was widely published, and many brides opted for white in accordance with the Queen’s choice.”