The given name Teegan is believed to have originated from the Irish Gaelic language. It is a variant spelling of the name Tadhgan, which is derived from the Old Irish word "taidh" meaning poet or philosopher, and the suffix "-gan" meaning little. The name Tadhgan was initially pronounced as "TIG-an" or "TEE-gan" in Irish Gaelic.

Historically, the name Teegan was found in ancient Irish records and manuscripts dating back to the 5th century. One of the earliest known bearers of this name was Saint Tadhgan, an Irish missionary and bishop who lived in the 6th century. He is venerated as the patron saint of several Irish dioceses.

In the Middle Ages, the name Teegan was particularly popular among Irish noble families and clans. A notable figure from this period was Tadhgan Ó Cearnaigh (c. 1315 - 1390), an Irish poet and historian who composed works in both Irish and Latin.

During the Renaissance period, the name Teegan gained popularity in various parts of Europe due to the influence of Irish scholars and missionaries. One such individual was Tadhg Ó Cianáin (c. 1570 - 1626), an Irish Franciscan friar and priest who played a significant role in the Counter-Reformation in Europe.

In the 19th century, the name Teegan was borne by several prominent figures in Irish literature and politics. One example is Teegan O'Regan (1794 - 1829), an Irish poet and patriot who wrote extensively about Irish nationalism and cultural identity.

Another notable bearer of the name Teegan was Tadgh O'Connor (1807 - 1861), an Irish politician and lawyer who served as a Member of Parliament in the United Kingdom and advocated for Irish independence.

While the name Teegan has its roots in Irish culture, it has since gained popularity in various parts of the world, particularly in English-speaking countries. However, it is important to note that the name's historical significance and cultural associations are deeply rooted in its Irish Gaelic origins.