Show ContentsDerment History, Family Crest & Coats of Arms

Today's Irish surnames are underpinned by a multitude of rich histories. The name Derment comes from the Irish Gaelic Mac Diarmada, which means "son of Diarmuid," or, son of Dermot and belongs to the venerable Irish tradition of patronymic naming. However another source claims the name came from the Irish diarmaid, which meant "the god of arms." 1

Early Origins of the Derment family

The surname Derment was first found in County Roscommon (Irish: Ros Comáin) located in central Ireland in the province of Connacht, where the family is believed to have been descended from the Heremon dynasty of Irish Kings and were known as the Princes of Moylurg, or the Kings of Connacht, known as the Clann Mulroona. Specifically they were descended from Teige, a King of Connacht and his son, Murtogh, Prince of Moylurg. Their ancient territories were in the counties of Roscommon and Galway. They were divided into three septs. One of the septs embraced English rule early and relatively painlessly, the other two suffered at the hands of Strongbow's invasion in the 12th century. Of the other two septs, the more prominent is based in Coolavin, in Sligo. This sept was originally found at Moylurg and controlled a large part of Roscommon.

"The MacDermotts were ancient Princes of Moylurg, having their territories in the Barony of Boyle, County Koscommon, and parts of the Parishes of Islandeady, Turlough and Breaffy, in Counties Sligo and Mayo. Their chief fortress "was on an island in Lough Key, near Boyle," and they were hereditary Marshals of Connaught. At the present time Connaught is the province in which the MacDermotts are principally found, and half of the persons of the name in that province belong to County Roscommon. " 2

The head of this branch was one of the few leaders who is still credited as an authentic chieftain by the Genealogical Office of Ireland, conferring the rightful title The MacDermot. Moreover, the chief is also unofficially styled Prince of Coolavin. The third sept held a family seat at Kilronan in the north of Roscommon, and was referred to as MacDermot Roe, from the word ruadh, which means "red."

Early History of the Derment family

This web page shows only a small excerpt of our Derment research. Another 119 words (8 lines of text) covering the years 1172, 1251, 1320, 1592, 1641, 1707 and 1717 are included under the topic Early Derment History in all our PDF Extended History products and printed products wherever possible.

Derment Spelling Variations

Within the archives researched, many different spelling variations of the surname Derment were found. These included One reason for the many variations is that scribes and church officials often spelled an individual's name as it sounded. This imprecise method often led to many versions. Dermott, Dermot, Dermitt, Dermit, McDermott, Dermutt, Dermut, MacDermott, McDermot, MacDermot, MacDermitt, McDermitt, MacDermit and many more.

Early Notables of the Derment family

Another 36 words (3 lines of text) are included under the topic Early Derment Notables in all our PDF Extended History products and printed products wherever possible.

Migration of the Derment family

The 19th century saw a great wave of Irish families leaving Ireland for the distant shores of North America and Australia. These families often left their homeland hungry, penniless, and destitute due to the policies of England. Those Irish immigrants that survived the long sea passage initially settled on the eastern seaboard of the continent. Some, however, moved north to a then infant Canada as United Empire Loyalists after ironically serving with the English in the American War of Independence. Others that remained in America later joined the westward migration in search of land. The greatest influx of Irish immigrants, though, came to North America during the Great Potato Famine of the late 1840s. Thousands left Ireland at this time for North America, and those who arrived were immediately put to work building railroads, coal mines, bridges, and canals. In fact, the foundations of today's powerful nations of the United States and Canada were to a larger degree built by the Irish. Archival documents indicate that members of the Derment family relocated to North American shores quite early: Jo Dermott who settled in Virginia in the year 1635 at the age of 21; John, Thomas, James, and William Dermot settled in Philadelphia, Pennsylvania between 1774 and 1804.



The Derment Motto +

The motto was originally a war cry or slogan. Mottoes first began to be shown with arms in the 14th and 15th centuries, but were not in general use until the 17th century. Thus the oldest coats of arms generally do not include a motto. Mottoes seldom form part of the grant of arms: Under most heraldic authorities, a motto is an optional component of the coat of arms, and can be added to or changed at will; many families have chosen not to display a motto.

Motto: Honor probataque virtus
Motto Translation: Honour and approved valour.


  1. O'Hart, John, Irish Pedigrees 5th Edition in 2 Volumes. Baltimore: Genealogical Publishing Company, 1976. Print. (ISBN 0-8063-0737-4)
  2. Matheson, Robert E., Special Report on Surnames in Ireland with Notes as to Numeric Strength, Derivation, Ethnology, and Distribution. Dublin: Alexander Thom & Co., 1894. Print


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