Regarding the "Lady Lavery" Irish Free State £50 banknote, Gawain O'Connor writes:

In 1928 the Currency Commission issued the first series of 'Free State' banknotes in seven denominations. Sir John Lavery wascommissioned to paint a portrait, symbolic of Erin, as their main feature. To this end, the artist reworked an earlier portrait of Hazel Lavery(1909), but dressed her as an archetypal colleen, with her arm resting on an Irish harp, and set her against a mountainous landscape.

The portrait appeared in full on the £10, £20, £50, and £100 notes. The lower denominations-10/-, £1 and £5 notes-featured just the head and shoulders. Thomas Bodkin, Director of the National Gallery of Ireland from 1927 to 1935, promoted Lavery's candidature to work on the banknote image. However, the artist always believed that it was President (Taoiseach) William Cosgrave, head of the Cumann na nGaedheal government, who suggested the idea in acknowledgement of Lavery and his wife's involvement in the Treaty (1921). He quoted Cosgrave as saying of the banknotes: 'Every Irishman, not to mention the foreigner who visits Ireland, will carry one next to his heart'.

To read the complete Portrait of Lady Lavery description, see:
Portrait of Lady Lavery as Kathleen Ni Houlihan, 1928 (http://onlinecollection.nationalgallery.ie/view/objects/asitem/342/2/)

To read the complete Artist's Studio description, see:
The Artist's Studio: Lady Hazel Lavery with her Daughter Alice and Stepdaughter Eileen, 1909-1913 (http://www.nationalgallery.ie/en/Collection/
Irelands_Favourite_Painting/Final_Lavery.aspx)

To read the earlier E-Sylum article, see:
http://www.coinbooks.org/esylum_v19n15a32.html (www.coinbooks.org/esylum_v19n15a32.html)