HEY YOU, YES, YOU. DID YOU KNOW WHAT THAT THE ANGLO-IRISH TREATY OF 1921 DIVIDED IRELAND INTO TWO REGIONS, THE IRISH FREE STATE, GIVEN COMMONWEALTH STATUS AND NORTHERN IRELAND WHICH STAYED PART OF THE UK. FIONA ALLISON. THE ANGLO-IRISH TREATY BROUGHT LITTLE PEACE TO IRELAND AFTER ITS IMPLEMENTATION: THE IRISH FREE STATE PLUNGED INTO CIVIL WAR.