County Roscommon: History
Rathcroghan (Irish: Rath Cruachán), near Tulsk, a complex of archaeological sites, the home of Queen Medb (Irish: Méadhbh, anglicised Maeve), was the seat of Kings of Connacht and then to the High Kings of Ireland. This was the starting point of the Táin Bó Cúailnge, or Cattle Raid of Cooley, an epic tale in Irish mythology. The county is home to prehistoric ringforts such as Carnagh West Ringfort and Drummin fort.
County Roscommon as an administrative division has its roots in the Middle Ages. With the conquest and division of the Kingdom of Connacht, those districts in the east retained by King John as "The King's Cantreds" covered County Roscommon, and parts of East Galway. These districts were leased to the native kings of Connacht and eventually became the county. In 1585 during the Tudor re-establishment of counties under the Composition of Connacht, Roscommon was established with the South-west boundary now alongside the River Suck.
A "well defined" and "original" fine metal workshop was active in County Roscommon in the 12th century. The Cross of Cong, the Aghadoe crosier, Shrine of the Book of Dimma and Shrine of Manchan of Mohill' are grouped together as having been created by Mael Isu Bratain Ui Echach et al., at the same Roscommon workshop. The workshop has been linked to St. Assicus of Elphin.
John O'Donovan (1806–1861), historian and scholar, visited County Roscommon in 1837, while compiling information for the Ordnance Survey. Entering St Peter's parish in Athlone in June 1837, he wrote, "I have now entered upon a region totally different from Longford, and am very much pleased with the intelligence of the people." However, he had major problems with place-names. He later wrote, "I am sick to death's door of lochawns, and it pains me to the very soul to have to make these remarks, but what can I do when I cannot make the usual progress? Here I am stuck in the mud in the middle of Loughs, Turlaghs, Lahaghs and Curraghs, the names of many of which are only known to a few old men in their immediate neighbourhood and I cannot give many of them utterance from the manner in which they are spelled."