Carrots were originally purple, white, and yellow in their wild forms.
The purple varieties were especially common in regions like Afghanistan, where carrots were first domesticated.
In the 16th–17th centuries, Dutch breeders selectively bred carrots to produce the orange variety we commonly see today.
This was done for taste, color, and uniformity, and some historical accounts suggest it was also in tribute to the Dutch Royal House of Orange.
The orange carrot gradually became more popular in Europe, eventually replacing many of the older purple and yellow varieties in common cultivation.