Ó Maoilriain is the correct form in the homeland of the great sept of Ryan, formerly Mulryan; but it is now usually abbreviated to Ó Riain, which is properly the name of a small Leinster sept. IF 260 etc; Map Tipperary (Mulryan) Carlow (O’Ryan)

(Celt;) the Irish O’Riain = Descendant of Rian, i.e. the Kinglet [v. O’-, and + ri, a king, prince + the genit. of the diminutive suff. -án]

(Irish) Descendant of the servant of the queen; grandson of Rian or Riaghan, or of a follower of Rian or Riagha.

This family were lords of Idrone, co. Carlow. The name was not unfrequently written O'MuIryan. O'Ryan, Prince of Idrone, was slain in 1170, by Raymond le Gros, the avant-courier of Strongbow. D'Alton.

The surname Ryan comes from the Irish O’Riaghain or O’Riain, respectively meaning ‘descendant of Riaghan’ and ‘of Rian’. Closely related are the names O’Mulrigan (anglicised from the Irish O’Maoilriaghain) and O’Mulryan (anglicised from the Irish O’Maoilriain). These latter Irish surnames mean ‘descendant of Maol-riaghain or Maol-riain’; the Maol- names mean ‘follower of Riaghan’ or ‘of Rian’. The meaning of the name O’Maoilriaghain is disputed, but the most likely explanation is that it means ‘devotee of St Iain’ (Iain being the Gaelic for John), or perhaps ‘Iain the Chief’.

The first name John is one of the most ancient in popular use. It derives from the Hebrew name Jochanaan (or Johanan) which means ‘God is gracious’. The Crusaders introduced the Latin form Johannes into Europe, and the name quickly spread. In each country it developed its own variations, from Jan in Holland to Jean in France. In England it became John, and in Scotland it became Jock (as well as Iain). The Welsh version is Evan (giving rise to the popular surname), and the Irish version is Sean (pronounced Shawn) indicating its similarity to the French Jean.

The Ryans are one of the great Irish family clans (or septs), and the name is found all over Ireland. It is most frequent in County Tipperary, where it is four times more popular than the other two best-known names from this county (O’Brien and Mahon). Variations on the original Mulryan are still found in Galway and Leitrim in the form of Mulrine and Muroyne. O’Riain is the more usual Leinster form.

Occasionally the name Ryan derives from an entirely diffeent source. Here the origin of the name as we know it is Ruane.

This comes from the Irish Gaelic ‘O’Ruadhain’, which derives from the Gaelic word ‘ruadh’ meaning ‘red’. Thus the first holders of the name would have been given it as a nickname, alluding either to their ruddy complexion or to their red hair. In the latter case an original ‘ruadh’ might well have been of Norse origin. Many of the Ryans in County Mayo derive their name from the Ruane source.

Dr James Ryan (1891—1970) was, with Eamon de Valera, a founder of the Irish political party, Fianna Fail, whose name means ‘Army of Destiny’.

In ancient Arthurian legend and romance, Ryance, King of Wales, Ireland and The Isles, cut the beard off every knight he vanquished and made the beards into a cloak. Finding him­self one short, he sent a messenger to King Arthur, demanding his beard and threatening to come and take it if necessary. Arthur refused and dispatched two knights who overcame Ryance and brought him back a prisoner.

Loch Ryan is an arm of the sea in southern Scotland, dividing the peninsula of Galloway from the mainland of Wigtownshire.

There are no name-related towns in the United Kingdom (but there is a Ryan lake) and few Ryans anywhere. The United States has 2 towns named Ryan and a Ryan Park township.

In England, Scotland and Wales Ryan is not common enough to be counted separately. In Ireland with about 34,000 name­sakes Ryan is the 8th most popular surname. Around the world Ryans are most common in Canberra (one in 460 families), Sydney (one in 571) and Melbourne (one in 600). In the United States there are an estimated 155,000 Ryans-making this the country’s 152nd most popular surname.