It was first used between 1845 and 1848 and officially adopted on June 23, 1972. Luxembourg had no flag until 1830, when patriots were urged to display the national colors. The flag was defined as a horizontal tricolor of red, white, and blue in 1848, but it was not officially adopted until 1972. The tricolor flag is almost identical to that of the Netherlands, except that it is longer and its blue stripe is a lighter shade. The red, white, and blue coloring was derived from the Grand Duke's coat of arms, which dates from the 13th century.