what's its purpose?
It is a collegiate body that defines the overall political directions and priorities of the European Union
European Council
The European Council ("informally" EUCO) is a collegiate body that defines the overall political directions and priorities of the European Union. 
who sits for ireland at the european council table UNANSWERABLE when was this council established? 1975
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European Council [SEP] Introduction
The European Council ("informally" EUCO) is a collegiate body that defines the overall political directions and priorities of the European Union. It comprises the heads of state or government of the EU member states, along with the President of the European Council and the President of the European Commission. The High Representative of the Union for Foreign Affairs and Security Policy also takes part in its meetings. Established as an informal summit in 1975, the European Council was formalised as an institution in 2009 upon the entry into force of the Treaty of Lisbon. Its current president is Charles Michel, former Prime Minister of Belgium.