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John, the youngest of five sons of King Henry II of England and Eleanor of Aquitaine, was at first not expected to inherit significant lands. Following the failed rebellion of his elder brothers between 1173 and 1174, however, John became Henry's favourite child. He was appointed the Lord of Ireland in 1177 and given lands in England and on the continent. John's elder brothers William, Henry and Geoffrey died young; by the time Richard I became king in 1189, John was a potential heir to the throne. John unsuccessfully attempted a rebellion against Richard's royal administrators whilst his brother was participating in the Third Crusade. Despite this, after Richard died in 1199, John was proclaimed King of England, and came to an agreement with Philip II of France to recognise John's possession of the continental Angevin lands at the peace treaty of Le Goulet in 1200.

When was John appointed the Lord of Ireland?
1177