Derrycassan is bounded on the north by Kilnavert and Corran townlands, on the west by Camagh, Sruhagh and Gorteen, Templeport townlands, on the south by Derryniggin in County Leitrim and Burren townland and on the east by Coologe and Toberlyan townlands. Its chief geographical features are Coologe Lake, Derrycassan Lake and Camagh Lough. Derrycassan is traversed by a public road and several rural lanes. The townland covers 498 statute acres.
History
Medieval
The earliest surviving mention of the townland name is Doire Casáin, which appears in an interesting list of the rents due to the McGovern Chief, Maghnus 'Ruadh' Mág Samhradháin about 1400 A.D. It reads as follows: From this list we see that in 1400 the main type of farming carried on in Derrycassan was milk and beef cattle together with sheep. A Roman poem from 91 A.D., the Thebaid by Publius Papinius Statius was translated into Irish as Togail na Tebe. This Irish version was transcribed in 1487 in Derrycassan by Diarmaid Bacach mac Parthalain, in the house of his father, Fineen mac Parthalain. The introduction to the translation translates as Diarmaid Bacach mac Parthalain also wrote or transcribed the following, some in Tullyhaw, probably in Derrycassan. Tochmarc Becfhola or The Wooing of Becfola. Irish translations of romantic tales, lives of saints and other religious texts. Dán do Chormac Mág Shamhradháin Easpag Ardachaidh. His brother Conall Ballach Mac Parthaláin was also a scribe. He produced part of the manuscript Rawlinson B 513 Bodleian Library, Oxford, England.
After 1600
The 1609 Baronial Map depicts the townland as Dirricasan. The 1652 Commonwealth Survey spells the name as Derrecassan. The 1665 Down Survey map depicts it as Derrycashan. In the Plantation of Ulster by grant dated 29 April 1611, along with other lands, King James I granted the two polls of Dirricassan to the McGovern Chief, Feidhlimidh Mág Samhradháin. The townland had been part of the McGovern chief's personal demesne for several hundred years before this and it was just a Surrender and regrant confirming the existing title to the then chief. This is confirmed in a visitation by George Carew, 1st Earl of Totnes in autumn 1611 when he states that Magauran had his own land given him on this division. An Inquisition of King Charles I of England held in Cavan town on 4 October 1626 stated that the aforesaid Phelim Magawrane died on 20 January 1622 and his lands including two polls of Derricassan went to his son, the McGovern chief Brian Magauran who was aged 30 and married. The McGovern lands in Derrycassan were confiscated in the Cromwellian Act for the Settlement of Ireland 1652 and were distributed as follows- The 1652 Commonwealth Survey lists the proprietor as John King & others. In the Hearth Money Rolls compiled on 29 September 1663 there were three Hearth Tax payers in Dirilussno- James Meeke, Robert Turner and Shane O'Killyn. A grant dated 1667 from King Charles II to James Thornton included 191 acres and two roods in Derrycassan. A grant dated 7 July 1669 from King Charles II to John, Lord Viscount Massareene included five acres in Derrychashen. A deed dated 8 June 1730 by John Johnston of Currin refers to lands in Derryhassan. The 1790 Cavan Carvaghs list spells the townland name as Derrycassar. In the 1825 Registry of Freeholders for County Cavan there were six freeholders registered in Derrycassan- Thomas Breden, Patrick Gannon, Francis Logan, Owen M'Dermott, Edward Maher and Myles Rorke. They were all Forty-shilling freeholders holding a lease for lives from their landlord. William Blashford of Lissanover. The Tithe Applotment Books for 1827 list one hundred and forty five tithepayers in the townland. In 1833 two people in Derrycassan were registered as a keeper of weapons- Thomas Bredin and William Lauder. The Derrycassan Valuation Office Field books are available for November 1839. Griffith's Valuation of 1857 lists sixty eight landholders in the townland.
The chief structures of historical interest in the townland are:
An earthen ringfort.
An earthen ringfort.
A crannóg in Derrycassan lake. An ancient stone axe was found there in 1935 and is now in the National Museum of Ireland.
A crannóg in Derrycassan lake.
A medieval Bullaun Stone is located in the townland, which local tradition claims is a cure for warts.
In 1863 a small, very perfect, copper battle-axe, 61 inches long, and 3 inches wide, with four rivets and an iron weapon-tool, adze-shaped on one side, and hatchet on the other, 9 inches long were found in Derrycassan.
