During the Imperial era, in the same fashion as the other imperial states of Europe, Wales had flags and coats of arms made to represent her overseas colonies.
The Empire was made up of colonies in South America, Africa and the Pacific.
Y America (The America's)
Wales' premier colony was also its most short lived. Carved from territory in South America, the province of Y Wladfa (Patagonia) existed in what is now Argentina. The second Welsh territory in south America was the island complex Ynys Iestyn and Ynysoedd Rhyngosod y De (OTL South George & South Sandwich). Administratively the islands were governed together as the Ynysoedd y De Iwerydd (South Atlantic Islands).
The African colonies of the Welsh Empire were spread over three Crown Colonies. The oldest colony was Gini which consisted of the OTL territory of Guinea and Guinea Biseau and the Crown Colony of Y Gambia. The Welsh Empire also held the territory of Sierra Leone. Together these three crown colonies made up Affrica Gorllewinol Cymraeg. The Empire also extended to two other crown colonies. The territory of Gini Gyhydeddol (Equatorial Guinea) which was governed as Affrica Gyhydeddol Cymraeg and the inland area around the African great lakes (OTL: Bwrwndi/Burundi) which was governed as Talaith Llynoedd Mawr Affrica (Great Lakes Province)
Tiriogaethau Cymraeg y Môr Tawel (Welsh Pacific Territories)
The Welsh territories in the Pacific were governed on a two tier basis. The Crown Governor held responsibility for the entire Welsh Pacific territory, with Lt Governors' in charge of the individual territories. The Kingdom of Tonga was a "protected state" and as such was not formally part of the Empire itself, though Wales held responsibility for all Tongan foreign affairs until 1970.