Cromadh was a village in the territory of the Uí Fidgenti, and one of the seats of the O’Donovans of the Ui Fidgheinte, which flourished from the late 4th century to the mid 12th century. A hermitage, Dísert Óengusa, was founded nearby by Óengus of Tallaght around the year AD 780. The townland is located on the River Maigue, which although now having a tidal flow only to Adare, in ancient years the river had a tidal flow past Croom, making it a transit route for the Viking ships traversing inland from the Shannon during the 9th and 10th centuries. Contacts arising along the Maigue River between Danish Vikings and the Ui Donnabhains provide an insight into the alliance between the two groups in the late 10th century. John O’Donovan claimed in an appendix to the Annals of the Four Masters that Croom derived its name from Ancrom O'Donovan Crom Ua Donnabáin, who was slain in Innis Beale Antha Dos in 1254, based on the similarity of Ancrom with Crom. However, that claim has been thoroughly discredited. The earliest mention of Cromadh in the historical annals was in 1151, when “A great predatory excursion was made by Ruaidhri, son of Toirdhealbhach Ua Conchobhair, into Thomond; and he carried away many cows, and burned Cromadh". This event took place only three years after Turlogh O’Brien, King of Munster in 1148, and whom alternatively allied with and opposed Rory O’Connor, defeated the Danes at the nearby fort of Rathmore. The burning of Croom in 1151 should be viewed in the larger context of leading powers continuing to punish and push the O’Donovans with their Danish alliances from their historical territory, which continued for another century as new Anglo Saxon powers arose from the Fitzgeralds, Butlers, Roches and whom competed with the O’Briens, O’Connors and MacCarthys for the Ui Fidgheinte territories. Ultimately, in the early 13th century, the lands surrounding Croom were given to the Fitzgeralds of Kildare. The Earls of Kildare continued to administer and build in the area of Croom through the end of the 16th century, and the competition for control of the Croom area was reduced to regional contests between the Earls of Desmond and the Earls of Kildare. Both houses associated their war cries with their territory: the war cry of the Geraldines of Kildare was Cromadh-abu, with various spellings Croom Abu. For comparison, the war-cry of the Desmond Geraldines was Seanaid-abu, associated with Shannid Castle, or Shannid Forever.
Places of interest
Croom is home to Croom Castle, rebuilt by the FitzGeralds and Fitzmaurices from an earlier O'Donovan fortress, which may or may not have first been destroyed. In any case, it was restored in the 19th century. In the 18th century, it was the meeting-place of the "Maigue poets." West of Croom are the ruins of a 15th-century church and a round tower, the top part of which is missing. To the east is Croom Hospital which began life in 1852 as a workhouse, and became a hospital in 1924. Along the river Maigue is a ruin mill along with a newer mill, built by Henry Lyons in 1788 and was operational until 1927. In late 2014, a new Civic Centre was opened which includes a restaurant, library, public computers and function hall.