Our Montgomerys are descended from Hugh Montgomery (known as Hugh Ballylessan Montgomery to distinguish him from a number of other Hugh Montgomerys) who was the son of George Montgomery , brother of the 2nd Viscount Montgomery of the Great Ards. George’s father was 1st Viscount and one of the leaders of the Plantation of Ulster. This very prominent and important family is described in The Montgomery Manuscripts by William Montgomery of Rosemount, writing in 1696 – 1706.
https://archive.org/details/montgomerymanusc00montuoft . This author was cousin of Hugh of Ballylessan Montgomery so knew the family personally and was writing a contemporary account. The account goes right back to the founding of the settlement in Ulster in the times of the Plantation in 1603.
Hugh married, first, Lavinia Mary Hunckes, only daughter of Col Hercules Hunckes. Their son was Hercules, after his mother’s father, who married Jane McNeill. It is this branch of the family that we are descended from. There were Hunckes living near John of Naas who called him ‘cousin’. (Col Hunckes has a fascinating story as he was one of those responsible for killing Charles I when Cromwell gave the order to have him killed, so he was known as ‘the regicide’. However, he apparently refused the order to kill the king so was subsequently pardoned. The Hunckes, later Hanks, family is a fascinating one and Abraham Lincoln’s mother was a Hanks.).
Hugh Ballylessan married, secondly, the widow of Lord Blaney, who was also related to and the widow of Hugh Willoughby of Carrow. He took the name of Willoughby to inherit his wife’s family manor house and lands of Carrow (a large estate in Co Fermanagh). His son Hugh Willoughby married a daughter of Earl Erne of Crom Castle on the banks of Loch Erne
http://www.nationaltrust.org.uk/crom . One of their daughters, Elizabeth, married into the family of the first Baron Mountflorence of Florence Court , John Cole,
http://www.nationaltrust.org.uk/florence-court ; Another daughter, Catherine, married Alexander Montgomery of Ballyleck, also associated with the Cole family. From
https://moultray.wordpress.com/tag/ballyleck/ : “Colonel Alexander Montgomery m. Elizabeth daughter and heiress of Colonel Thomas Cole of Ballyleck prior to 1696 and died march 25th 1722 leaving several children. It was probably early in this century that Alexander and his cousin appeared to have disused the Hessilheid arms and to have adopted the shield of the Montgomeries as carried by the Earls of Eglington, adding thereto instead of the Scottish crest an arm in armor the hand grasping a broken spear and for a motto instead of the Scottish “Guarde Bien”, the new words “Patrise Infelici Fedelis”. “
(This is the coat of arms and crest used by John Montgomery of Naas as seen in his house at The Knocks. This suggests that his father William was in touch with his cousins and adopted the Ballyleck version of the crest.)
The third daughter married Cromwell Price, and their daughter married a McNeill cousin, descendent of Hercules and Jane.