The coat of arms of Saint Vincent shows peace and justice represented by two women, one holding an olive branch (peace) and the other making a sacrifice over an altar (justice). This design with the Latin motto “Pax et justitia” (“Peace and justice”) was used as a flag badge on the British Blue Ensign when Saint Vincent was an associated state of the United Kingdom from 1969 to 1979. At independence on October 27, 1979, however, a national flag designed by Elaine Liverpool was introduced. The arms were shown on a green breadfruit leaf, recalling the introduction of breadfruit in Saint Vincent by Captain William Bligh. The background of the flag consisted of vertical stripes of blue, yellow, and green separated by narrow white stripes.
Many believed this complex and expensive flag to be inappropriate. Following June 1984 elections won by the New Democratic Party, Prime Minister James Mitchell commissioned a new flag. Swiss graphic artist Julien van der Wal created a version with the narrow white stripes omitted, leaving a simple vertical tricolour of blue-yellow-green. The arms and breadfruit leaf, difficult to distinguish at a distance, were replaced by three green diamonds arranged in the form of a V. They suggest three gems (the islands are known as the “Gems of the Antilles” or the “Jewels of the Caribbean”), and the V shape is an indirect reference to the first letter of Vincent. The colour symbolism is unchanged from the original flag. Green is for the rich vegetation of the islands and the vitality of their people; yellow stands for golden sands and personal warmth; and blue is for sea and sky. The new flag was officially hoisted on October 22, 1985.
Source: Britannica