Ireland's best-known Irishman, his name and signature in every household and village in Ireland, and many abroad, is also the least known. Part of Dublin life for over two centuries, both family and brewery have passed into legend, but their origins have been obscured. Here, in the round, these origins are explored and the story of the man and his background told for the first time. Various sources are examined and myths about Arthur laid to rest, many of which were allowed to continue by his descendants. This narrative traces the family's origins in Ulster, Gaelic and Protestant-Irish tenant-farmers from humble backgrounds on both sides, when Arthur's father Richard appears as a household agent in Celbridge, Co. Kildare, in 1722 to work for Arthur Price, the Protestant Dean of Kildare. In 1755 Arthur takes on a brewery in Leixlip and joins the Kildare Friendly Brothers dining club in 1758, marrying and moving to St James's Gate in 1759/60 where the business developed. By 1781 he is a patriarch and member of liberal 'patriot' political groups, diversifying his assets to preserve his wealth in unsettled times. Of a generation with Edmund Burke and Richard Brinsley Sheridan, this wily businessman built an empire that endured and expanded. Family and social history combine with an account of the brewing process and descriptions of economic and political backgrounds in a rapidly developing Ireland, giving a rich weave to this tapestry. Visual sources include maps, rare original documents, prints, and photographs of associated houses and places, people, and artifacts. The result is a fascinating contextual portrait of an enigmatic figure, the founding father of one of Ireland's most powerful dynasties.