The flag was flown by ships of the Thirteen Colonies in North America before the American Revolution. Modification of the flag was used to express the discontent of the colonists before and during the outbreak of revolution. This can be seen in both the Taunton flag and the George Rex flag. It also formed the basis of the Grand Union Flag of 1775, which served as the first American national flag, although it differed slightly from the primary Red Ensign in that it had a squared Union Flag in the canton.