MacShane is a patronymic surname originating in Ireland. The surname evolved from the given name Shane, a derivative of John, of Hebrew origin. Early records spelled the name Mac Seáin or Mac Seagháin. Historically, the MacShanes from Ulster are a branch of the O'Neills, while in County Kerry, the surname was adopted by the Fitzmaurices. MacShane is uncommon as a given name. This surname was also the name given to the group of sons of Shane "An Diomas O'Neill", Prince of Ulster, Lord O'Neill, and Chief of all the O'Neill clans from 1558-1567. When he died, his ten or more sons were spread out among family within Ulster and Scotland. In the early 1580s they regrouped and for nearly a decade battled with their O'Neill cousins for dominance of Ulster and their father and grandfather's estate, the Earldom of Tír Eoghain. The English officials used the term "the Mac Shanes" (the sons of Shane) as an all encompassing term to describe many sons that made up this army in Ireland. Two specific families in Ireland, both descendants of Shane O'Neill, kept the nickname as a surname; the MacShanes in modern southern County Londonderry, and the MacShanes of Mayo. Over time both shortened their surname to McShane, and then eventually translated the name to Johnson (Shane is Irish Gaelic for John). Major General Sir William Johnson had his surname developed in this method. In the past century, the use of McShane as a surname in Ireland, Scotland, and Australia has overtaken Johnson. Sons of Shane Shane had at least ten sons by his various wives. All of these ten are considered legitimate, but there may be others of a base origin. Many of them were later fostered in various O'Neill clans after their father's death, and eventually became the rival force to Hugh O'Neill in his climb to power in the 1580-1600 timeframe. His known sons are: Shane Og, mother was Catherine MacDonnell. He died in 1581 on a raid, was O'Neill tanist in 1579. Henry MacShane O'Neill, His mother was Catherine MacDonnell, he died 1622. Father of Sir Henry O'Neill and Con Boy McHenry. Perhaps the most famous of Shane's sons. Granted a large Estate in Orior County Armagh. Conn MacShane O'Neill, died in 1630. Mother was either the daughter of Shane og Maguire or Catherine MacLean, sources disagree. He invaded Ulster in 1583 with 3000 Scottish warriors and was