St. Andrew is the patron saint of Scotland and also the patron saint of Greece, Russia, and Romania. He was the brother of the first Catholic Pope, St. Peter, and one of the first apostles of Jesus. [1] Andrew is said to have been killed in Patras, Greece. He requested the Roman authorities who sentenced him to death not to let him be crucified in the same position as Jesus. His request was approved, and he was ultimately executed on an X-shaped cross (St. Andrew's Cross or X-shaped Cross), so the X-shaped Cross later became his symbol.

The flag of Scotland is the blue and white St. Andrew's cross flag (i.e. the flag of St. Andrew's cross on a colored background) × The cross shaped pattern is derived from St. Andrew, a Scottish saint who was crucified on an X-shaped cross.
The connection between St. Andrew and Scotland originated from two legends. One is that it is said that the relics of the saint were brought by St Regulus from Patras to Kinrymont in Fife in the 4th century, and later his ship sank on the east coast. Afterwards, Kinrymont's church became St. Andrew's Cathedral and gradually developed into an important center for medieval pilgrimage. Another version is that in the 9th century, due to the appearance of an X-shaped cross in the sky before Athelstaneford's victory in war, King Angus Mac Ferguson of Pickett regarded St. Andrew as his patron saint.

According to relevant information, St. Andrew became the patron saint of Scotland around 1000 AD. In 1286, the front of the Scottish Guard seal bears the Saint Andrew pattern nailed to an X-shaped cross, as well as the Latin inscription Andrea Scotis Dux Eesto Compatriotis - "Saint Andrew is the leader of all Scottish compatriots.". In 1390, during the reign of Robert III, St. Andrew was first inscribed as a national symbol on a 5-shilling coin.
St. Andrew's Day is November 30th every year, but it is not a public holiday in Scotland.

According to historical records, a battle occurred near Athelstaneford in 832 AD, which prompted people to start using the St. Andrew's Cross as the national flag of Scotland. Under the leadership of King Angus Mac Fergus of Alba, Pickett and the Scottish coalition invaded the Northumbrian territory of Lothian. In this battle, Angus's army was surrounded by a larger number of Anglo Saxon and Saxon armies and faced the danger of failure. Unfortunately, the Chinese king asked the monks to pray for divine will. Not long after, when Angus saw a sight like the St. Andrew's Cross in the deep blue sky, he believed it was God's will for him. So the king immediately swore that if St. Andrew helped him win, then from then on St. Andrew would become the patron saint of Scotland, and his cross would become the flag of Scotland. Angus truly achieved victory, and the St. Andrew's Cross became the flag of Scotland as expected.
Regardless of whether it is divine intent or not, the St. Andrew's Cross flag was widely used in the 14th century, but it was not fixed to use blue as the base color. In fact, it was not until the 16th century that the St. Andrew's Cross flag with a blue background and a white cross was finally formed. Throughout the 17th century, especially in the army and navy, the St. Andrew's Cross was a symbol of the country, and it was also incorporated into the flag of the United Kingdom during the unification of England.
However, in 1707, Congress decided to abandon the use of the St. Andrew's Cross flag, and it was not until the second half of the 20th century that it was reintroduced. Now, it has become the legal flag of Scotland again, used by all Scottish participating teams in international competitions, and the flag is also flying on flagpoles in front of most public buildings, sometimes alone, and sometimes together with the flag of the United Kingdom. Due to its simple design, many private and public groups also use it as an element of corporate identity.

In 2003, Scottish officials prescribed the color of flagpoles and clarified the specific tone of St. Andrew's Cross Blue. From then on, the blue color requirement is based on the Pantone 300 in the international color standard system, and the white Saint Andrew's cross is reflected on it. However, this standard is still not a mandatory requirement, and the St. Andrew's Cross flag can continue to have a variety of colors as the base color.

In 1997, a memorial center for the St. Andrew's Cross was opened in a restored small building next to the Athelstaneford Church. Here, people can learn more about the St. Andrew's Cross, and even understand its origin from a short audiovisual clip. This commemorative center is open to visitors for free from 10am to 5pm every day from April to September. The memorial hall has been encouraging people to visit since its opening in 1965. The flag of St. Andrew's Cross will always fly in the wind above the memorial hall, even at night, it will continue to fly in the light.