The name Bryna is believed to have its origins in the Celtic languages spoken in ancient Britain and parts of modern-day France. It is thought to be derived from the Proto-Celtic root *brig, meaning "high" or "exalted." This root is also found in the names of many hills and mountains across the Celtic regions of Europe.

In its earliest recorded form, the name appeared as Brigina or Brigina in texts from the 5th century CE, referring to a Celtic goddess associated with poetry, healing, and metalworking. This goddess, known as Brigid or Bride in Irish mythology, was widely revered across the Celtic world.

The name Bryna itself first appears in historical records from the 9th century, borne by a Welsh noblewoman named Bryna ferch Gwriad, who lived in the kingdom of Powys. Another early bearer of the name was Bryna of Rosslyn, a 12th-century Scottish noblewoman who was a patron of the arts and a renowned poet in her own right.

Throughout the Middle Ages, the name Bryna was relatively uncommon but can be found scattered across various records and chronicles from Britain and Ireland. One notable example is Bryna ab Owain, a 14th-century Welsh bard and poet who was celebrated for her intricate poetic compositions.

In more recent history, the name Bryna has been borne by several notable individuals, including:

1. Bryna Fireside (1885-1957), an American actress and vaudeville performer who appeared in several Broadway productions in the early 20th century.

2. Bryna Wasserman (1909-2000), a Canadian social worker and activist who dedicated her life to advocating for the rights of children and families.

3. Bryna Pauker (1926-1998), a Romanian-born American artist and sculptor known for her abstract and figurative works in various media.

4. Bryna Zionts (born 1941), an American mathematician and academic who made significant contributions to the field of operations research and optimization theory.

5. Bryna Fifield (born 1957), an American author and journalist who has written extensively on topics related to women's health and wellness.

While the name Bryna has never been among the most popular given names, it has maintained a consistent, if modest, presence throughout various cultures and time periods, carrying with it a connection to the rich heritage of the ancient Celtic world.