Following Mac Murchada's death in May 1171, Strongbow succeeded him as King of Leinster and, once again, Magnus joined the High-King's coalition army to oust the Normans, however their forces were routed during an unsuccessful siege of Dublin. Fearing that Strongbow was growing too powerful and might set up his own independent kingdom in Ireland, Henry II of England landed in Ireland in October 1171 to establish control over both the Irish and the Normans. Henry's campaign in Ireland was largely successfully and he managed to reign in the Normans as well as a few Irish kingdoms which also submitted to him. Most crucially, he retained the city of Dublin, and Baron Hugh de Lacy was made its bailiff. Henry's appointment of de Lacy was intended to act as a counterbalance to Strongbow. However, in order to achieve this, de Lacy would need a strong holding on Irish soil and it was decided that the Kingdom of Meath was to be granted to de Lacy.