County Leitrim no relation County Roscommon
Geography
Leitrim is the 26th of the 32 counties by area  (21st in size of the 26 counties of the Republic) and the smallest by population. It is the smallest of Connacht's five counties in both size and population. Leitrim is bordered by the counties of Donegal to the north, Fermanagh to the north-east, Cavan to the east, Longford to the south, Roscommon to the south-west and Sligo to the west. Fermanagh is in Northern Ireland while all the other neighbouring counties are within the Republic of Ireland.
Leitrim has a hilly and mountainous landscape in its northwest and is relatively flat in the southeast, each separated from the other by Lough Allen in the middle of the county. Leitrim has the shortest length of coastline of any Irish county that touches the sea. At Tullaghan, the coastline is only 4.7 kilometres (2.9 mi) long.  The Shannon is linked to the Erne via the Shannon–Erne Waterway. Notable lakes include:History
In ancient times Leitrim formed the western half of the Kingdom of Breifne. This region was long influenced by the O'Rourke family of Dromahair, whose heraldic lion occupies the official county shield to this day. Close ties initially existed with the O'Reilly clan in the eastern half of the kingdom, however, a split occurred in the 13th century and the kingdom was divided into East Breifne, now County Cavan, and West Breifne, now County Leitrim. The Normans invaded south Leitrim in the 13th century but were defeated at the Battle of Áth an Chip in 1270.
Much of the county was confiscated from its owners in 1620 and given to Villiers and Hamilton. Their initial objective was to plant the county with English settlers. However, this proved unsuccessful. English Deputy Sir John Perrot had ordered the legal establishment of "Leitrim County" a half-century prior, in 1565. Perrott also demarcated the current county borders around 1583.
no relation