Northern Uí Néill in Ulster and later, the Ua Conchobhairs of Connacht. An Sligeadh Timcheall In 1101, officially High King of Ireland and with the Church on his side, Muirchertach planned his largest and most ambitious campaign yet, called An Sligeadh Timcheall ("The Circular Hosting"). He gathered the armies of the various kingdoms, save those of Ulster, and marched northwards. The six-week long campaign began with his army marching north to the River Erne at Assaroe, then to the Inis Eoin Peninsula, burning Ardstraw and Fahan on the way. The offensive culminated with the destruction of Grianan an Aileach, an important fort of the Northern Uí Néill, in revenge for Ua Lochlainn's earlier burning of towns in Munster. Muirchertach famously ordered his men to bring back one stone from the walls of the fort for every sack of provisions they had. They marched home to Munster along the ancient route of Slige Midluachra. For the first time during his reign, he had successfully subdued the Ulaid. The Northern Uí Néill had been severely weakened, but did not capitulate. Muirchertach would lead several campaigns against Ua Lochlainn over the next few years, but was unable to gain their submission, with the campaign almost always ending in stalemate in southern County Armagh. With the Ulaid now under his control, however, he had another angle from which to attack the Uí Néill from in the Northeast, and easier access to the Hebrides and other areas of the Isles, and parts of Scotland. Campaigns in the North and Second War in the Irish Sea Like many of the High Kings of Ireland from the South had found, including Muirchertach's great-grandfather Brian Boru, the last place to recognise their authority was Ulster, namely the Kingdoms of Ulaid and the Northern Uí Néill. At the turn of the century, Muirchertach led annual campaigns against Domhnall Ua Lochlainn and the other northern kings, with mixed success. Muirchertach's armies consisted of soldiers from every Irish Kingdom apart from Ulster. The fighting was often heavily concentrated in what is now modern southern County Armagh, but Muirchertach would often be halted by the intervention of the comrade Patraic, the abbot of Armagh, who would organise truces between the two kings. Muirchertach attempted a campaign against the Cenél Chonaill, with naval support from the fleet of Dublin, but he was forced to retreat following the destruction of the Dublin fleet. Around