It's unclear exactly where green enters the equation. Many people had previously opposed the usage of blue as a national Irish color, but the strongest green appeared in the Confederation of Ireland's flag (the era during which the Catholic bishops and noblemen tried to oust the Protestant powers from Dublin). This flag was used from 1973 to 1977. In more recent years, green has been used as a border between the Republic of Ireland and Northern Ireland.
There are several theories about why green was chosen as the national color of Ireland. One theory is that it represents the green fields that would have covered much of Ireland had it not been for the arrival of the white man. Another theory is that it represents the green hills surrounding Dublin and other cities, while a third theory is that it's because everyone likes green food (spinach, lettuce, potatoes) and drink (beer, wine).
The modern-day flag of Ireland was adopted in 1986 and includes the same green-white-blue pattern as the previous flag but with an addition of a harp symbol on the blue field. The harp is the official emblem of Ireland and appears on all government documents, stamps, and coins. It also colors the road system in Ireland, most notably along the Pottinger Way in Southern Ireland which is named after Robert Pottinger, 1st Baron Pottinger who advocated for its construction in 1770.
Green became connected with Ireland in the 1640s, when the Irish Catholic Confederation employed the green harp banner. Green has long been connected with insurrection and was the unofficial color of Ireland. In the late 18th century, green became connected with nationalism once more. The Young Irelanders adopted it as their color in 1848.
The connection between Ireland and green dates from at least 1641, when Oliver Cromwell's army took possession of the city of Dublin after its surrender to them by Irish leader O'Neill. They painted the houses they occupied black, but left some white walls exposed as a sign of peace. This is why today, buildings over 300 years old are still used for educational purposes in Ireland.
In the 1720s, King George I of England ordered that all soldiers stationed in Ireland wear green uniforms to distinguish them from other British troops. This is the origin of today's image of the Irish soldier as we know him: green beret, green jacket, green trousers. These colors were later adopted by the nationalist movements in Ireland, and today represent solidarity among supporters.
The first national flag of Ireland was created in 1652 by James Croft, who was appointed Commander of the Forces in Ireland by the king. He chose red and blue as the main colors of the flag, with the red symbolizing blood spilled for religion and the blue representing the Irish Sea.
Wearing green in honor of Ireland on St. Patrick's Day is said to be auspicious. "The green in the tricolor represents Catholics in the Irish flag, which was first brought to Ireland in 1848," Kinealy explains. (Orange denotes Protestants, while white indicates peace amongst them.)
In Ireland, wearing green on any other day than March 17 is considered bad luck.
However, it is not recommended for someone who is trying to become pregnant or is already pregnant.
Furthermore, if you are trying to get a job in the agriculture industry, it is best not to wear green.
Finally, don't wear red or blue on St. Patrick's Day; these colors are used instead.
The Irish tricolor, Ireland's flag, does not feature blue and instead serves as a reminder of Ireland's more recent past. The green represents the nationalist (Catholic) population, the orange the Protestant (Unionist) population, and the white in the middle depicts the peace between the two. The color scheme is an adaptation of the British flag which was used before 1801 when Ireland was part of the United Kingdom.
During the 1916 Easter Uprising, the green flag was used by revolutionaries who wanted to create an independent nation of Ireland. Today, it is considered a sacred symbol by many Catholics because it reminds them of Jesus' crown of thorns and his suffering. It also has spiritual significance for Protestants because they believe it would have been destroyed if Catholicism had won out during the English Revolution of 1640.
After World War II, Catholic priests began using green lights instead of red candles on Christmas trees to represent hope for a better future after years of poverty caused by economic discrimination against Catholics.
In addition, green is important to Ireland because it is one of the few colors that can be used in both the national flag and the traditional St. Patrick's Day color.
Blue is used in the Irish flag to represent loyalty and justice. Orange is the color of celebration in Ireland because it reminds people of the victory of the Irish over the Saxons at the Battle of Aughrim in 1691.