History of Meath 1845 Version.

...                              The Parliamentary Gazetteer 0f Ireland 1844-1845 Vol.2.
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Meath, an ancient extensive territory,first a kingdom, and finally a lordship or earldom, partly within the present province of Ulster, but chiefly identical with most of the northern part of the modern province of Leinster. It seems to have comprehended the present counties of Meath, Westmeath, and Longford, the greater part of the present King's county, and small parts of the present counties of Cavan and Kildare; and to have been, in consequence, somewhat more extensive than the territory of the modern diocese of Meath. It probably was either erected into a kingdom in the second century, or was then made the peculiar domain of the Irish monarchs, while the other ancient divisions of the island owed them only feudal obedience; and it contained at Teamor, now called Tara, between Navan and Dunshaughlin, the residence of the monarch of Ireland, the seat of the supreme government, and the place where St. Patrick is alleged to have performed the first of his series of grand acts for establishing Christianity on the overthrow of paganism.
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The monarchy of Ireland was afterwards separated from the kingship of Meath, and became so weakened by the separation as to retain little more than a nominal supremacy; but though the kings of Meath, now ranked as subordinate princes, and no longer boasted the possession of the chief government of the island, they continued to wield nearly absolute regal power, and constituted one of the two lines of the great family of O'Neills, who alternately swayed the sceptre of all Ireland. The kingdom was originally or uncorruptedly called Midhe or Miadhanagh, and, in Latin, Midia; and Beauford says, in the eleventh number of the Collectanea,
“According to several Irish poems and manuscripts, Midhe, in the early and middle ages, was, as at present, divided into two parts, that is, east and west; the eastern part, or East Meath, was denominated Oircamhoin, or eastern country, and the western part, or West Meath, Eircamhoin, whence the Hereman of the Irish poems and romances.”
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The kingdom of Meath, so rich in the greater part of its soil, and so destitute of natural fastnesses, offered a tempting and an easy booty to the Danish invaders; and it, in consequence, suffered often and severely from their descents and excursions. Turges, a Danish adventurer, in the early part of the 9th century, traversed the whole length of the kingdom, established his power on the shores of Lough Ree, and fearfully ravaged large portions of both Meath and Connaught; but he was eventually captured and slain, in the vicinity of Mullingar, by Melaghlin, then king of Meath, and afterwards monarch of Ireland. The Danes, however, soon renewed their incursions, took advantage of the civil dissensions of the Meathmen, and, during several centuries, vied with hostile princes among the native Irish in making Meath a field of strife, and a theatre of spoil and disaster. Melaghlin 11, king of Meath in the time of the celebrated Brian Boromh, held the monarchy of Ireland, abdicated it in favour of Brian, resumed it after Brian's death, and retained it thence till his own death about 150 years before the Anglo Norman invasion; and he was the last monarch of all Ireland of the family of O'Neill, or royal line of the house of Meath. O'Melaghlin, king of Meath, one and a quarter century after the death of Melaghlin II., had, in common with other princes, been reduced into subordination by Dermod MacMurrough, king of Leinster, and had given his daughter in marriage to O'Rourke, king of Brefny; and when MacMurrough vilely abducted that lady, O'Melaghlin, aided by other princes, and even by MacMurrough's own subjects, hurled the royal abductor from his throne, and drove him into ignominious retreat to England, where he unprincipledly sold himself to the scheme of the Anglo Norman invasion.
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Immediately after the speedy subsequent conquest of Ireland, Hugh de Lacy received from Henry 11, a grant of Meath as a county palatine or feudal lordship, with several regal rights; and he parcelled out the territory among his followers, in portions which were afterwards recognised as baronies from the circumstance of his making their proprietors barons. This great lordship, however, appears to have been speedily wrenched from the English by the Irish; but it was reconquered by De Lacy, after his second appointment to the governorship of Ireland in 1178; and, during the general rebellion which arose out of the mal administration of Prince John, afterwards King John, it was preserved from a second return to Irish control by means of a victory won over the Irish forces in 1186 by William Petit. Hugh de Lacy, the second, or son of the first Hugh de Lacy, fought, as Earl of Meath, in a contest between two Irish princes for the sovereignty of Connaught, was appointed to the governorship of Ireland, and executed with difficulty a commission to arrest and send to England John de Courcey, the Anglo Norman Earl of Ulster. De Lacy was rewarded for his services with the earldom of Ulster, and was succeeded by his brother Walter in the earldom of Meath; and both of them became turbulent and insubordinate, and involved their territories in intestine commotions, and in contests with the Crown, and with the lords of the English Pale.
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At the death of Walter, Meath was divided into West and East, and inherited by his two daughters: Westmeath became the portion of the elder daughter, the wife of Sir Theobald Verdon, and was allowed to fall away, for upwards of a century, into a state of total alienation from English law; and East Meath became the portion of the younger daughter, the wife of Sir Geoffry Genneville, but speedily passed by forcible capture into the possession of native chiefs or Anglo Norman lords. In 1329, the English were severely defeated by the native Irish in a pitched battle near Mullingar. In the reign of Henry VI., Richard, Duke of York, and lord deputy of Ireland, erected castles along the border of Meath for its protection. In the reign of Henry VIII., Con Buckagh O'Neill invaded Meath, but withdrew at the approach of an army under the lord deputy, the Earl of Surrey. In 1539, the insurgent Irish destroyed Navan, mustered their forces at Tara, and when on their march thence, were overtaken and dispersed. In 1540, the native Irish rose in great strength in Westmeath to march upon the English Pale; but, on learning that they were likely to be hotly received, they dispersed. Very nearly at the end of the reign of Henry VIII., Meath, which hitherto had been preserved in its ancient territorial integrity as one county, was divided into the two counties of Meath and Westmeath; but the former of these included the portion of the present county of Cavan which had belonged to the ancient Meath, and the latter included the present county of Longford, and a large part of the present King's county; and the final arrangement, or that which now exists, was made in the reign of Elizabeth.
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The history of the county of Meath, down to near the close of the reign of Henry VIII., is that of successively the kingdom, the lordship, and the county palatine of Meath. During the rebellion of 1641, the English entered Trim, made it a military post, defeated an attempt of the Irish to take it by surprise, and made it the theatre of negociations for concluding a peace with the insurgents. In 1647, Trim was unsuccessfully besieged by General Preston; in 1649, it became an asylum to some of the royalists, who were beaten at Rathmines in the county of Dublin; and after the capture of Drogheda, and the massacre of the garrison of that town by Cromwell, it was without resistance surrendered to the parliamentarians. In 1690, the famous battle of the Boyne, so prolific of momentous consequences to the whole of the three kingdoms, and in a sense, to Europe, was fought principally on the north border of Meath; and the retreat and the pursuit of respectively the defeated and the victorious armies, were conducted right through the eounty from north to south. In the rebellion of 1798, a party of insurgents committed some outrages at Dunboyne, suffered a defeat at Ratoath, and cut off a portion of their victors at Clonee Bridge; other insurgents committed outrages at Dunshaughlin; and a body of about 4,000 took post at Tara, and suffered there a sanguinary defeat from the troops and the yeomanry.