The Tudor conquest of Ireland proceeded by surrender and regrant, whereby a Gaelic lord would surrender sovereignty to the English monarch as monarch of Ireland, and be regranted title to the land under common law. The 1580s shiring of Ulster proceeded on that basis, with McMahon's country becoming County Monaghan, within which Dartraighe became the barony of Dartree; likewise Clann Ceallaigh became Clankelly barony in County Fermanagh. Ballyconinsi was shired with the McMahons rather than their enemies the Maguires. Most of the Gaelic proprietors in these counties forfeited their lands after the Nine Years' War or the Rebellion of 1641. In 1640, most of Ballyconinsi was owned by one Jacob Leirrey, with small tracts retaining Gaelic owners.