This monograph is devoted to the study of the prerequisites of the Irish uprising of 1641-1652. and its initial period - before the formation of the Irish Confederation in October 1642. It ends with a brief overview of the main events of the uprising that occurred after this date. The history of the Irish Confederation and the war between England Ireland before 1652, in all its aspects of domestic and international importance for both Ireland England, is a complex set of problems that are still waiting to be investigated.