The name Kirstyn is a variant spelling of the feminine given name Kirsten, which is derived from the ancient Norse name Kristin. Kristin itself comes from the Latin name Christiana, meaning "a Christian" or "a follower of Christ." This name was originally used among early Christian communities in Europe during the Middle Ages.

The earliest known written record of the name Kristin dates back to the 12th century in Scandinavia, where it was commonly used in countries like Norway, Sweden, and Denmark. It's believed that the name spread throughout Northern Europe during the Viking Age, as Norse explorers and settlers brought their names and cultural traditions with them.

One of the earliest recorded examples of the name Kirstyn can be found in the 13th century, when a Norwegian woman named Kirstyn Hakonsdatter was mentioned in historical records as the daughter of King Håkon IV of Norway. She lived from around 1234 to 1262.

In the 16th century, a woman named Kirstyn Sorensdatter was recorded as being one of the first European settlers in Greenland, having arrived there in 1578 with her husband and children. She is notable for being among the earliest known European women to give birth in the Arctic region.

Moving forward to the 17th century, Kirstyn Tovey was an English woman born in 1620 who became one of the first settlers in the British colony of Virginia. She arrived in Virginia in 1635 and is recorded as having lived in the Jamestown settlement.

In the 18th century, Kirstyn Gordon was a Scottish noblewoman who played a role in the Jacobite risings, which were a series of uprisings aimed at restoring the House of Stuart to the British throne. She was born in 1718 and was known for her support of the Jacobite cause.

Another notable figure in history was Kirstyn Delafield, an English painter and artist who lived from 1787 to 1858. She is remembered for her portraiture and landscape paintings, many of which are held in collections in Britain.